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ASPHALTS 

Their Sources and Utilizations 
1914 ROAD EDITION 

Containing Five New Chapters on 

MODERN ROAD CONSTRUCTION 

BY 



T. HUGH BOORMAN, C.E. 

Consulting Engineer and Asphalt Expert 
Secretary, Am. Soc. En. Ar. C. 



PRICE, TWO DOLLARS 



NEW YORK 

THE WIIJJAM T. COMSTOCK CO. 
1914 













Copyright, 

1908,1914 

BY 

T. Hugh Boorman 




M -3 1916 



g)CI.A420l56 



CONTENTS 

Chapters 

I. — Discovery and Early Use of Asphalt. 

II. — Rock Asphalt Mastic or Asphalt Coule. 

III.— Trinidad Asphalt. 

IV. — Petroleum Residuum and California Malthas as a Fluxing Material. 

V. — Venezuela Asphalts. 

VI. — Cuban Asphalts. 

VII. — American Bituminous Limestone. 

VIII. — Bituminous Asphalt Sandstone Rock. 

IX. — Manjak and Uintaite. 

X. — Late European Work. 

XI. — Turkish and Other Bitumens. 

XII. — Developments of Asphalt Industry up to 1903. 

XIII. — Asphalts in 1908. 

XIV. — Asphalt in Building Construction. 

XV.— Dustless Roads. 

XVI. — Methods of Surfacing Roads. 

XVII. — Asphaltic Oils, Their Classification and Properties. 

XVIII. — Application of Asphaltic Oils. 

XIX. — Sprinkling with Asphaltic Oils. 

XX. — Latest Views of Engineers on Asphaltic Surfacing. 

XXI. — Municipal Asphalt Plants. 

XXII. — Asphalt Waterproofing. 

XXIII.— Asphalt in Roofing. 

XXIV. — Asphalt for Manufacture. 

XXV. — Asphalt Machinery. 

XXVI. — Rock Asphalt Maintenance. 

XXVII.— Asphalt Macadam Roads. 

XXVIII.— Cold Laid Asphalt Roads. 

XXIX. — Bituminous Road Surfaces. 

XXX.— Asphalt Block for Roads. 



PREFACE 

TIS book was suggested by a series of articles that appeared some years 
ago in Architecture and Building. Since the numbers containing these 
articles ran out of print, there has been a continuous call for them, 
and the request was made that they be issued in book form. 

The great advance of late in the asphalt industry has called for a com- 
plete manual on the subject. This the author has endeavored to furnish, so 
that architects, engineers and students in the technical schools and municipal 
officers having charge of road construction may have a reliable reference 
book on the subject. 

As will be seen, many new features in the exploitation and utilization of 
asphalt have arisen during the first eight years of this century; and un- 
doubtedly the greatest demand yet known is still to come for the purpose of 
surfacing dustless roads. This line of work is very fully treated of, and, to 
the author's mind, is the question of the day. 

I have endeavored, without fear or favor, to give credit to all producers 
of asphalt in every country and clime and to give to all their due. I have 
made no comparisons of asphalts as against other materials, although some 
of my sources of information may have incidentally given statements showing 
the superiority of asphalt over other materials for waterproofing, etc. 

This book is the result of thirty-six years of active life among asphalt 
mine owners, refiners, importers, exporters, manufacturers and contractors, 
and, as will be seen, has taken me to many countries, in all of which I have 
endeavored to glean information from all interested, from presidents of 
corporations to the humblest stirrer of an asphalt kettle. 

To give due credit to all to whom I am indebted for information would 
well nigh call for an additional volume. At the risk of seeming ungrateful 
to the many, I wish to record special obligations to the late Leon Malo, C. E., 
and his coadjutor W. H. Delano, C. E., to the "Good Roads Magazine," 
"Municipal Engineering," and other technical journals; principally to the 
efficient, painstaking officials of the Bureau of Public Roads of the Depart- 
ment of Agriculture, whose work in helping the people of the United States 
to utilize their opportunities for building "goods roads" in the various sections 
of the country cannot be too highly spoken of; and last, but not least, to my 
worthy publisher, W. T. Comstock, and to my son, Kitchell Monckton 
Boorman. 

T. HUGH BOORMAN. 

New York. Sept. 14, 1908. 



PREFACE TO SECOND EDITION 

Since the first edition of "Asphalts" went to print, there have bee» 
three International Conventions on Road Construction, held respectively 
at Paris, Brussels and London. 

Conventions of National, State and minor sections have been too 
numerous to mention; the knowledge disseminated at these many meetings 
has been extensive and interesting. The general tenor of the discussions 
has created a heavy demand for asphalts of all descriptions and the com- 
mercial interests involved are now very heavy. Some of the older known 
asphalts have become discredited to a great extent and the user of asphalt* 
has now many opportunities of purchasing materials, capable of meeting 
any specifications drawn by conscientious engineers. 

I have been frequently asked if I made any statements in the 1908 
edition which I should wish now to modify. I am glad to state that I 
can stand today for everything I wrote that year. 

Along the line of road work many developments have taken place, and 
in the five new chapters of this edition I have striven to give some of the 
new methods of construction evolved since 1908. 

I have endeavored by attending conventions, college and engineering 
society's lectures, and by careful reading of the technical journals, and by 
revisiting England, to keep in touch with all improvement in street and 
road construction which have been developed since the time of the first 
edition. 

In the immense amount of treatises and papers on bituminous con- 
struction presented before conventions, engineers' associations and colleges, 
it is lamentable to find how few can be received as from unbiased sources. 
This is the day of astute advertising, and in addition to their regularly 
paid employes, such as consulting engineers, chemists and salesmen, the 
large corporations subsidize to an immense extent the daily and technical 
press so that the unsuspecting layman seeking information on asphalt, is 
apt to be misled through statements of merits of individual brands of 
asphalts, emanating from such clever salesmen with their various titles 
ranging from college professors to daily news reporters. The most flagrant 
advertising dodge was that of an asphalt company who offered a premium 
of $100 to be awarded to the highway college student who produced the 
best treatise on asphalt. 

A recent clipping from an unknown source affords an interesting if 
not instructive statement of the use of asphalt in "ye olden tymes" : 

There was nothing slow about the ancient Romans. They used a cement 
the formula for which many a manufacturer would be glad to have. They 
built roads so costly as to make the modern politician green with envy. 
They even were acquainted with asphalt and bitumen. Tacitus, writing 
about 55 B. C, describes this material as follows: 



"At a stated season of the year, the lake throws up bitumen. Experi- 
ence, the mother of all useful arts, has taught men the method of gathering 
it. It is a liquid substance, naturally of a black hue, and by sprinkling 
vinegar upon it, it floats on the surface in a condensed mass, which those, 
whose business it is, lay hold of with the hand, and draw to the upper 
parts of the vessel; thence it continues to flow in and load the vessel, till 
you cut it off. Nor could you cut it off with brass or iron. It shrinks 
from the touch of blood." * * * 

T. HUGH BOORMAN. 

Nsw York, April 25, 1914. 



Chapter I. 
DISCOVERY AND EARLY USE OF ASPHALT. 



CONSIDERING the importance of the subject little has been 
published in regard to the material known by the generic 
name of asphalt. A few books and many short papers read before 
engineering societies, prepared for technical journals or for the cir- 
culars of asphalt companies, comprise, generally speaking, the litera- 
ture on the subject. These have been written almost exclusively 
by engineers in the employ of special companies or others finan- 
cially interested in particular asphalt deposits or mines, and so 
necessarily have dealt with the subject within a much confined 
limit. 

It is proposed in this book to discuss the various kinds of 
asphalt and their adaptability for different methods of construction. 
In the first place all disputes on the nomenclature of asphalts must 
be avoided and the fact conceded that the hydro-carbons, viz., as- 
phalt, bitumen, and maltha, are synonymous, while differing in 
chemical composition. I am the more anxious to take this ground, 
as in going back to the earliest times in which asphalt is known to 
have been used it is necessary to refer to the mineral pitch, or bitu- 
men, as being the material quoted. The first use of asphalt spoken 
of was the cementing in the erection of the Tower of Babel ; next 
we read that Noah pitched the Ark within and without, "bituminabis 
cum bitumine," says the Vulgate, and also in Genesis we read, "Et 
asphaltus fuit eis vice cimenti." The great law-giver, Moses, was 
preserved from death at the suggestion of the Egyptian Princess, in 
a basket rendered waterproof by bitumen. 

Felltham wrote in the beginning of the 17th century of the 
"Bituminated walls of Babylon;" the source of its supply, the 
fountains of Is, on a tributary of the Euphrates, still yields asphalt. 

Xenophon in his Anabasis speaks of the Median Wall as being 



10 



ASPHALTS. [chap. i. 



built of "Burnt brick laid in asphalt." Diodorus Siculus describes 
the process of laying the walls of Nineveh with material from the 
same source. He says : "In order to bind the bricks they were cov- 
ered with a layer of asphalt, instead of simple tempered clay, and 
were arranged in courses, and between each thirteenth course a bed 
of reed canes was introduced." Diderot's Encyclopedia attributes 
the burning of Sodom and Gomorrah to the accidental ignition of 
petroleum or bitumen, but the word petroleum not having been 
known to ancient writers, the legend probably refers to maltha or 
bitumen. Other ancient authors mentioning asphalt were Herod- 
otus, Aristotle, Strabo, Pliny and Homer. 

The Egyptians made extensive use of bitumen; it was spread 
upon the bandages wound around their mummies, and its wonderful 
preservative properties can be seen in our museums, where so many 
of their illustrous dead now have their abiding place. Asphalt was 
also used by the Egyptians in the foundations of the Pyramids, and 
for the coating of the external and internal walls of the ground 
floors of houses, and in the construction of cisterns, silos and other 
work where waterproofing was necessary. Therefore, from be- 
fore the time of the Deluge, asphalt has been used and referred to, 
and it is no new subject to be considered. 

During the Middle Ages we read nothing of its use, and not 
until 1 72 1 do we hear of a treatise on asphalt being written by 
Eyrini d' Eyrinis, professor of Greek, doctor of medicine, in which 
he wrote in a half serious, half-humorous manner of its uses for 
building purposes, and claimed it as a panacea for almost every 
sickness. This treatise, I understand, was reprinted by M. Leon 
Malo, C. E., the most able exponent of the Rock Asphalt industry, 
and to whose works I shall have to refer frequently. 

The asphalt beds, or mine, which were discovered by Dr. 
d'Eyrinis in 1710 were those of the Val de Travers, in the Canton 
of Neuchatel. The doctor recommends the material, describing it 
as "Peculiarly suitable for covering all kinds of construction, to 
protect wood and stone work against decay, worms and the ravages 
of time, rendering them almost indestructible, even when exposed 
to wind, wet and extreme variations of temperature." 

d'Eyrinis succeeded in using it with good effect for the lining 
of cisterns and walls, as a cementing material, and for the flooring 
of warehouses, etc. 

After some time the material fell into disuse; the quarries of 




'ASPHALTS' 



DISCOVERY AND EARLY USE. II 

\ al dc Travcrs were even forgotten, and it was not till the year 
1832 that the material was again prominently and successfully rein- 
troduced; the credit on this occasion being given to the Count 
Sassenay, and in 1838 the first asphalt sidewalks were laid in Paris. 
The rock asphalt seems to have been used in its mastic form for 
sidewalks and floorwork up to the year 1854, when M. Vaudry laid 
the first compressed rock asphalt roadway in Paris. The earliest 
knowledge of the adaptability of asphalt for this purpose seems, 
from M. Malo's account, due to the perspicuity of a Swiss engineer, 
M. Merian, who, in 1849, found that in summer the pieces of rock 
that fell from the carts in traversing the road between the mine and 
the mastic works at the village of Travers compressed under the 
wheels ; he put this lesson to profit by constructing a macadam road 
of crude rock asphalt, which was compacted with a roller. In spite 
of the instability of its foundation and the irregularity of its main- 
tenance the road was reported by M. Malo as in good order in 1866. 
From the Rock Asphalt Mines, therefore, it may be considered 
that there was started the great industry of asphalt street pave- 
ments, which add so much to the appearance and health of our mod- 
ern cities. Under these circumstances it seems only right to first 
take up the subject of Natural Rock Asphalt. It was, I believe, 
first brought prominently before the notice of the American Engi- 
neers by Mr. Edward P. North, C. E., who, in a paper read on 
April 16, 1879, before the American Society of Civil Engineers, on 
"The Construction and Maintenance of Roads," gave his impression 
from observation and information acquired by him on the subject 
of asphalt streets in London and Paris. 

Compressed Neuchatel rock asphalt was, however, laid in New 
York, in Union Square, in 1872, the writer having taken part in 
the actual work of laying it. This pavement, however, owing to a 
lack of heavy traffic, did not prove a success, and some ten years 
later it was replaced with asphalt mastic, which was partly manu- 
factured from the old rock pavement. The original company laying 
the work became financially embarrassed and went into the hands 
of receivers, and it was under orders of the latter that four blocks 
of Natural Rock Asphalt streets were laid on Pennsylvania avenue, 
Washington, with Neuchatel rock in 1876. This pavement, how- 
ever, not having any company to look after its maintenance, was 
repaired with Trinidad asphalt mixture, with which material eventu- 
ally it was entirely resurfaced. 



12 ASPHALTS. [chap. i. 

Three or four years later the Neuchatel Asphalt Company, of 
London, owners of the. Val de Travers' concession, sent over as 
their representative the late Captain Henry R. Bradbury, who 
supervised the laying of Neuchatel rock pavement in front of the 
Brevoort House and Hotel Victoria, on Fifth avenue, New York; 
his successor in the American management, Mr. Robert Butcher, 
found that the prices attainable for the work here did not compare 
favorably with those obtained in European cities, and has not fol- 
lowed up street pavement work. 

In 1892 the Compagnie Generate des Asphalte de France es- 
tablished a model rock asphalt plant at Long Island City, and un- 
der the management of the author from 1895 to I 9 00 some 28,000 
square yards of compressed asphalt were laid in New York, and 
about 15,000 square yards in Brooklyn. During this period a large 
amount of rock asphalt was also supplied from the Seyssel and 
Ragusa mines for use on streets in Philadelphia, Boston and Mon- 
treal. 

The generally recognized standard European rock asphalts are 
those of Seyssel, in the Department of Ain, France, and the Val de 
Travers, in the Canton of Neuchatel, Switzerland. Important de- 
posits are now being operated at Ragusa, Sicily; four companies 
are working adjacent mines, viz. : The Val de Travers Asphalt 
Paving of London, the United Limmer & Vorvohle Rock Asphalt 
Co., the Societa Sicula per L'Explotazione Dell Asfalta Naturale 
Sicilians, Palermo, and H. & A. B. Aveline Catania, exporting large 
quantities to Europe and America, their shipping ports being Maz- 
zarelli, Syracuse and Catania — other deposits are found at Mons, 
Department of Gard, France; Lobsann, in Alsace; Limmer, near 
Hanover, Germany; San Valentino, Province of Chieti, Italy; 
Maestu, in Spain, and in several parts of the United States, which, 
of late, having become quite an important feature in the asphalt 
industry, will be considered in full in a subsequent chapter. Mr. 
W. H. Delano, of Paris, in his "Twenty Years' Practical Experi- 
ence of Natural Asphalt and Mineral Bitumen," published in 1893, 
gives the analysis of natural rock asphalt as follows: As mined, 
the rock should be of a chocolate color, fine in grain, evenly im- 
pregnated with bitumen, free from sulphur, pyrites, clay, sand and 
of other extraneous matter. When examining with microscope 
always look at a fresh fracture. Rich Val de Travers rock, con- 
taining, say 11 to 13 per cent, bitumen, should be mixed with equal 




'ASPHALTS' 



DISCOVERY AND EARLY USE. 13 

parts of fine Seyssel rock containing 7 per cent, of bitumen, which 
is fixed and invariable, producing thus : 

11 + 7 

=g per cent, powder, suitable for a climate like that of Lon- 

2 
don. The same may be done with Ragusa (Sicilian rock), which is 
rich in bitumen of excellent quality, only the texture or grain of the 
limestone is loose, whereas that of Seyssel is fine and dense. Mons 
and St. Jean de Marejols asphalts are similar in structure to Ra- 
gusa, but the limestone is much finer. 

The rough and ready way of testing rock asphalt is to dissolve 
a sample of its powder taken from three-ton bulk, in carbon bisul- 
phide, turpentine, or ether. After stirring this well with a glass 
rod, strain it through a thick paper filter; then let the sulphide 
evaporate, which it will do at 70 degrees ; weigh the bitumen and the 
residuum, afterwards washing the latter in hydrochloric acid, which 
will cause the lime to effervesce, leaving any residue of silica, 
pfyrites, etc. ; but for an absolute test an analyst accustomed to 
hydro-carbons should be called in. 

In connection with this the following tables, showing the 
comparative analyses of asphalts, are given on the next page. 
They were prepared by Col. James W. Howard, B. L., C. E. 

The rock asphalt industry may be divided into two branches. 
The "comprime," or compressed work, and the "coule," or mastic 
work. For streets the compressed asphalt is used. The rock in its 
crude condition is placed in a crusher and reduced to small pieces 
and then passed through a disintegrater and reduced to a powder ; 
it then passes through a twenty-mesh sieve, nothing being added to 
or taken from the powder obtained by grinding the bituminous rock. 
The powder should contain not less than 9 per cent, of natural bitu- 
men. The powder is then heated in a suitable apparatus to 200 de- 
gress to 250 degrees Fahrenheit, and must be brought to the street 
at a temperature of not lss than 180 degrees Fahrenheit in carts 
made for the purpose, and carefully spread to such depth that after 
having received its ultimate compression it will have a thickness 
of two inches. The surface is rendered perfectly even by tamping, 
smoothing and rolling with heated appliances of approved design. 
This surface should invariably be laid on a foundation of six inches 
of Portland cement concrete. 



14 



ASPHALTS. 



[chap. i. 



Table I. 



ANALYSES OF CRUDE ASPHALTUM FROM A FEW COUNTRIES, ETC. 

California. Cuba. 

Bitumen 38 to 85% 24 to 68% 

Mineral matter 60 to 8 73 to 26 

Organic matter 1 2 to 1 

Water 2 to 6 1 to 5 

Total per cent... 100% 100% 100% 100% 



Mexico. 
35 to 94% 
55 to 4 

8 to 2 

2 



Trinidad. 
35 to 40% 
41 to 26 
10 to 4 
14 to 30 



Venezuela. 
45 to 95% 
40 to 2 

7 to 1 

8 to 2 



100% 100% 100% 100% 100% 100% 



ANALYSES OF ASPHALT ROCK FROM A FEW COUNTRIES, ETC. 



California. 
Various. 



Indian Ter. 
Various. 



Kentucky. 
Various. 
% 
4. to 10.70 



Bitumen 6.47 to 29.60 3.0 to 12.30 

Calcium Carbonate 9.10 80.00 

Silica 89.73 to 45.40 96.90 to 4.43 95.63 to 89.30 

Alumina, etc 15.90 0.10 to 

Magnesium carbon- 
ate 

Miscellaneous ... 3.80 



1.11 



1.86 
0.30 



0.37 



Texas. 

Various. 

% 

3.11 to 11.65 

90.30 to 0.03 

88.32 

6.0 

0.3 

0.29 



Utah. 

Various. 

% 

6.34 to 36.28 

8.02 to 29.52 

82.87 to 6.46 

27.74 



2.77 



Total per cent 100% 100% 100% 100% 



100% 100% 100% 100% 100% 100% 
J. W. HOWARD, B. L., C. E. 



Table II. 



♦CLASSIFICATION AND LOCATION OF CERTAIN 

COMPOUNDS. 



IMPORTANT BITUMENS AND 



GLANCE-PITCH, ASPHALTUM, MALTHA. ASPHALT AND BITUMINOUS ROCK. 



Pure or Nearly Pure 
(with Small Per 
Cent, of Mineral and 
Organic Matter). 

Argentina. 

Barbadoes. 

China. 

Cuba. 

Egypt. 

Equador. 

Honduras. 

Japan. 

Mexico. 

Russia. 

Syria. 

Turkey. 

United States. 

Venezuela. 



Compounded with Compounded with 
Limestone (Contain- Sandstone (Contain- 
ing Silicates, etc.). ing Carbonate of 
Lime, etc.). 



Compounded with 
Earthy Matter 
(Large Per Cent, of 
Silicates, Alumina, 
etc.). 

Argentina. 

Australia. 

Barbadoes. 

China. 

Colombia. 

Cuba. 

Egypt. 

Equador. 

France. 

Germany. 

Honduras. 

Japan. 

Mexico. 

Peru. 
* Russia. 

Syria. 

Trinidad. 

Turkey. 

United States. 

Venezuela. 

♦From Paper on "ASPHALTUM" by J. W. Howard of New York, 
of the American Society of Municipal Engineers. 



Austria. 

Cuba. 

France. 

Germany. 

Hungary. 

Italy. 

Russia. 

Sicily. 

Spain. 

Switzerland. 

Turkey. 

United States. 



France. 

Germany. 

Italy. 

Russia. 

Sicily. 

Spain. 

Turkey. 

United States. 



at convention 



Chapter II. 
ROCK ASPHALT MASTIC OR ASPHALT COULE. 



ROCK asphalt mastic, or asphalt coule, as it should more prop- 
erly be called, forms a most important branch of the asphalt 
industry, Dr. d'Eyrinis was its first exponent, and so far as I know 
Dr. Jeno Kovacs the last, the latter, in his report on asphalt read 
in 1901 before the Budapest congress of the "International Associa- 
tion for the Testing of Materials." The term mastic I must state 
is most misleading, and I fail to find how the term originated. The 
word is French, not English. The Anglican noun "mastic" dis- 
tinctly applies to the resinous substance obtained from the mastic 
tree, or to a kind of mortar composed of finely-ground oolitic lime- 
stone mixed with sand and litharge and used with a considerable 
portion of linseed oil; hence frequent confusion when the word 
mastic is used in specifications. The French word "mastic" is used 
for cement, and is more applicable. Still, with the innumerable 
cements used in construction, it would seem better to refer to 
coule, or melted asphalt, when speaking of the use of asphalt in 
other than its powdered form. The preparation of asphalt coule 
is as follows : 

The rock, after being reduced to a powder, is placed in cylin- 
drical kettles, in which about 8 per cent, of Trinidad asphalt has 
previously been placed and melted. The mass is stirred by revolv- 
ing arms and agitators at a temperature of about 350 degrees F. 
for about nine hours. It is thus thoroughly "cooked," and is then 
run out of the kettles into moulds, where it cools in the form of 
cakes or blocks, weighing from 56 to 60 pounds each. These are 
stamped with the brands of the mines. The mastic so prepared 
should show an analysis about as follows: 

Bitmumen 14-50 per cent. 

Carbonate of lime 85.00 " " 

Silica, alumina and oxide of iron. .50 " " 



100.00 



16 ASPHALTS. [chap. ii. 

To use it for walks or floors the blocks are broken up and again 
heated in suitable kettles and mixed with fine gravel or sand and 
Trinidad in the following proportions: 

Mastic blocks (broken) 60 lbs. 

Trinidad asphalt 4 

Fine gravel and sand 36 



100 



This is ''cooked''' for about five hours at a temperature of about 
360 degrees F., great care being taken constantly to stir the mix- 
ture. It is then taken out of the kettle by the bucketful and poured 
on the foundation prepared, its consistency being such that it will 
flow very slowly. It is then spread by means of wooden trowels 
and compressed and smoothed by rubbing, as in plastering. Soon 
after the introduction of asphalt coule in Paris it was introduced 
into the United States by a Philadelphia architect. The floors of 
the portico of the old Philadelphia Merchants' Exchange were laid 
with it about the year 1838, as stated by me in my paper on "Asphalt 
in Building Construction," read before the Brooklyn Architectural 
Students' League., May 14, 1890. Subsequently the War Depart- 
ment imported the material for covering the arches over casements 
and magazines in some of the forts, of which Fort William, on 
Governor's Island, was one. The great fire in Boston in 1872 first 
drew my attention to the desirable qualities of asphalt as a fireproof 
covering for roofs, and I introduced its use there in 1873. That 
this material is a most effective fireproof protection should be 
recognized. 

In 1835 a number of the inhabitants of the city of Bordeaux 
certified that at the time of the conflagration of the Bazaar Borde- 
lais, which happened on December 28th of that year, a number of 
burning beams, rafters and other bodies in flames fell on that part 
of the building covered with asphalt without causing it to melt, and 
further attested that the said roof so covered had not been injured 
to any material degree. Of the great fire in Hamburg in 1842, 
which destroyed, with other buildings, the Church of St. Nicholas, 
the London "Times"' of the 28th of May of that year, said : 

"It was remarked as a singular circumstance during the con- 
flagration that roofs covered with asphalt, of which there are some 
here, opposed rather than encouraged the progress of the flames. 





h i, l,|J. 



9 BrRNUVEmsOH. 



CITY HALL, PHILADELPHIA. 
Roofs and corridors laid with Asphalt Coule by The Vulcanite Paving Company. 



'ASPHALTS' 



ROCK ASPHALT MASTIC. 17 

It was imagined on account of the substance of which these roofs 
were composed that they would easily catch fire and be the cause 
of great mischief. Such, however, was not the case, for it appears 
that the fire had little or no effect on them, and when the roofs of 
the houses fell in, the asphalte, in which a sort of rubble is mixed 
up, was found to have resisted the effects of the heat, and, like a 
mass of dirt, served rather to smother the flames than to give them 
increased vitality." 

Very exhaustive tests were made for The Omnibus Co. of 
Paris in 1868 by MM. Flachat and Noissette, who submitted the 
results to the French Society of Civil Engineers. The insurance 
companies in the United States give special rates where asphalt 
is used for roofs. 

The specifications usually read: 

"For roofs on concrete , foundations properly leveled and 
graded, lay one inch of Seyssel or Neuchatel rock asphalt mastic, 
applied in two coats, on three thicknesses of roofing felt cemented 
with asphalt." 

Copper flashing should always be specified in connection with 
this roofing. The roof of the Philadelphia City Hall was laid by 
the Vulcanite Paving Co. with asphalt mastic, and the same material 
was used in the corridors of the building. The use of asphalt coule 
is by no means confined to roofs ; it is a desirable material for con- 
struction, from the damp course in the foundation of a building to 
the roof on the top of the same. Used as a damp course in the foun- 
dation, it arrests absolutely the capillary attraction that is. so fatal 
to many buildings and renders them unhealthy through dampness. 
Cellars should be floored with asphalt so as to insure dryness and 
health. 

As flooring for use in hospitals, lavatories, laboratories, laun- 
dries, refineries and mills it stands without a peer. It is impene- 
trable by moisture ,and will not crack from settlement of masonry, 
as will rigid and unyielding substance like artificial stone made 
from cement. Its characteristic of elasticity allows it to take up 
the varying strains and settlements that will occur in any masonry 
without cracking. Used as a foundation under heavy machinery, 
it absorbs all vibration and makes possible the mounting of the 
heaviest machinery in closely crowded quarters. As a flooring for 
railway stations, it will stand without cracking or splitting the im- 
pact of heavy blows from the dropping of baggage; it is not slip- 



l8 ASPHALTS. [ch*ap. II. 

pery, and can be laid in a monoltihic sheet without joints, which 
cannot be said of artifical stone. It is particularly recommended 
for breweries, paper mills, pulp mills, laundries and other floor sur- 
faces, which from the nature of the business are frequently wet and 
covered with water. It will not rot; it has no joints; no water 
can leak through to damage ceilings or goods stored in lower floors. 

Under usual circumstances one inch of asphalt mastic will 
stand any ordinary traffic. In exceptional cases, however, such as 
in wash houses and racking cellars of breweries, a thickness of one 
and a half to two inches is advisable. 

For cellars and floors for light business purposes three- 
quarters of an inch will suffice. 

Asphalt floors are preferably laid on concrete three inches thick, 
or in case of fireproof construction of hollow brick arches concrete 
leveled off about half an inch above the iron beams. Still, asphalt 
can be laid with advantage on wooden floors, in which case felt 
paper is laid on the boards to prevent any trouble from warping of 
the wood. One of the largest fields for the use of asphalt coule is 
for park walks. For nearly a quarter of a century the Park De- 
partment of New York has used this description of pavement, and 
with the exception of Madison Square, every park from the Battery 
to St. Mary's, in the Bronx, has had almost its entire walk areas 
finished with an asphalt surface. 

In view of the satisfaction that this work has given, it may be 
well to give the specification prepared by the department engineer, 
who, after calling for a foundation of three inches of Portland 
cement concrete, says : 

"After the base has been prepared as specified, and with its sur- 
face clean and dry, a layer of Seyssel or Mons, Neuchatel, Sicilian 
or Limmer asphalt mastic, in no place less than one inch in thick- 
ness, after having received its ultimate compression, is to be placed 
upon the base, carefully and evenly compressed with the proper 
tools for that purpose, and the finished surface to be free from de- 
pressions and truly and evenly surfaced to the finished grades and 
crown of the walk. The asphalt mastic to consist of natural bitu- 
minous limestone rock (i) from the French mines of Seyssel or 
Mons, equal in quality and composition to that mined by the Com- 
pagnie Generate des Asphalte de France; (2) from the Swiss mines 
at Val de Travers, equally in quality and composition to that mined 
by the Neuchatel Asphalt Co., Ltd.; or (3) from the Sicilian mines 



ROCK ASPHALT MASTIC. 



19 



at Ragusa and the German mines at Limmer, equal in quality and 
composition to that mined by the United Limmer and Vorwohle 
Rock Asphalt Co., Ltd., mixed with fine, clean grit and refined bitu- 
men, in such proportions and in such manner as to insure work that 
shall be sound and free from cracks and impervious to moisture 
under all climatic changes, and so as not to flow or spread in sum- 
mer or crack or disintegrate in winter, and as shall be directed by 
and to the satisfaction of the engineer." 

Rock asphalt coule has been used for many other purposes 
than in building and for sidewalks. The latest use I have seen 
was for medallion plaques. Among the larger calls for this ma- 
terial is that for reservoir linings. Municipal Engineering in one 
of its issues describes the construction of one in Astoria, Ore., 
where the bottom was covered with 6 inches of concrete 
containing 0.9 cu. yd. of crushed rock, 0.5 cu. yd. of gravel, 0.1 
cu. yd. of sand and one barrel of Portland cement per cu. yd. cut 
in blocks of 20 ft. square, with y 2 -mch asphalt joints, and this was 
covered with a ^-inch cement mortar finish and two coats of 
asphalt, one soft and the other harder, and together a little more 
than one inch thick. The slope had 6 inches concrete, 2-3-inch 
asphalt, a layer of brick and a second layer of asphalt 0.5 inch 
thick. The most common practice is probably from 18 to 24 
inches of clay puddle under concrete or paving. 

One of the large pieces of work in this line was the coating 
of the Queen Lane Reservoir, Philadelphia, where an area of 
235,000 square yards was surfaced in 1896 under the direction of 
Mr. John C. Trautwine, C. E. In 1897 tne reservoir at Coates- 
ville, Pa., with a capacity of 2,000,000 gallons of water, was aban- 
doned on account of excessive leakage, but having been lined with 
Neuchatel coule in that year, has been in use and given perfect 
satisfaction ever since ; this work was done under the direction of 
Mr. Alexander Potter, C. E., of New York, who also had the 
Phoenixville, Pa., reservoir lined with Seyessel asphalt in the year 
1898. 

In connection with asphalt coule a desirable combination of 
iron with asphalt has lately come into use. This construction has 
been adopted by the Fire Department of New York for stalls in 
engine houses ; it has been used for the space inside street railroad 
tracks and one foot on the outside. The pavement consists of cast- 
iron frames or gratings embedded in asphalt. The frame prevents 



20 ASPHALTS. [chap. ii. 

the asphalt from creeping and from wearing into holes or grooves. 
The frame is cast in the form of curved or undulating bars and 
crossbars, with stubs at the point of intersection. These frames 
are entirely embedded in asphalt, presenting a plain asphalt sur- 
face as in any ordinary pavement. Even under heavy traffic the 
asphalt wears down only to the stubs. Even when worn the sur- 
face shows a minimum of iron and a maximum of asphalt surface. 
When by such wear the stubs become exposed, the best course is, 
by the use of surface heater, to lay asphalt about half an inch in 
thickness upon the surface, which makes the pavement as good as 
new. At all times the presence of the iron frame prevents the 
forming of ruts or grooves, even under the influence of summer 
heat and heavy traffic, and the laying of a new asphalt coating 
upon worn pavements may be postponed for a considerable period 
after the iron stubs are exposed, and until a convenient time for 
making the repairs, the frame in the meantime preventing the 
destruction of the pavement by wear. 

This device is protected by patents. In connection with pat- 
ents it is interesting to note that the first patent in connection 
with asphalt was taken out by Admiral, the Earl of Dundonald, in 
185 1, for the employment of Trinidad asphalt and mineral bitumen 
of the North American Colonies in the production of artificial 
stones and other useful objects. He acquired land in La Brea, 
Island of Trinidad, which still remains in the hands of his family, 
and the Dundonald property is today contributing material for our 
city streets. 

Other English patents include Pym's composition, patented 
in 1855, which was composed of 5 cwt. of asphalt, 5 cwt. of chalk 
or limestone, 1 lb. of sal ammoniac, and as much coarse sand and 
grit as will mix freely with the above ingredients when heated in 
a cauldron; the heated mixture is then cast into the desired forms, 
and if extra toughness is required, cocoanut fiber, shavings, or 
other fibrous materials must be well incorporated. 

In RowclifT's patent (1855, pt- 2 > 906), the asphalt is reduced 
to small particles, and compressed by hydraulic or other pressure 
into the desired shapes ; sand or powdered stone may, if necessary, 
be added to it before compression. 

Sheil's stone, patented in 1867, consisted of small stone ce- 
mented together with asphalt. 

R. Skinner's patented asphalt blocks are prepared as follows: 



r3 



ET > 

2 H 



& "3 

•On.. 



P M 



O 

2 > 
R m 

II 
i 2 



&p 




'ASPHALTS' 



ROCK ASPHALT MASTIC. 21 

800 lbs. of asphalt are placed in an oven and submitted to sufficient 
heat to drive off water and easily volatized matters. In a short 
time the material is capable of being easily powdered, and in this 
state it is introduced into a large revolving cylinder heated up to 
200 degrees Fahr., and then are added 300 lbs. each of pulverized 
slag, coke, and limestone, and about 20 gallons of mineral tar. 
The tar should be previously boiled to expel water, and thoroughly 
mixed with limestone before being added to the other ingredients. 
After mixing and heating, the product is conducted from the re- 
volving cylinder to a revolving pan and the temperature lowered 
to 150 degrees Fahr. ; in this state it is placed in molds and sub- 
jected to heavy pressure. 

Tucker, an American patentee, also compressed mixtures of 
slag and asphalt into blocks. 

Fottrel's patent in 1873, pat. 3,086, prepares an artificial stone 
especially adapted for making drains, pipes, etc., by boiling to- 
gether a mixture of 13 cwt. of finely powdered stone, 4 gallons of 
shale oil, 2 cwt. Trinidad asphalt, and 2 cwt. bituminous rock. 
When thoroughly mixed, the composition is run into suitable 
molds. 

M. Leon Malo patented in France in 1873 his asphalt corn- 
prime blocks which have so long been in use in that country and 
which recently have been in great demand in Cairo, Egypt. 

Wilkinson's patent Trinidad asphalt blocks, generally known 
as the "Hasting" blocks, seem up to the present to have had the 
monopoly of such construction in this country and South America. 

For quite a number of years these blocks were made of lime- 
stone, but in 1893 trap-rock was substituted for the limestone. 
Blocks made of this latter material give much better satisfaction 
on account of the greater durability of the trap-rock, and at the 
present time that material is being used entirely in the manufac- 
ture of the blocks. Asphaltic cement is mixed with the trap-rock 
in proper proportions at a temperature of about 300 degrees. The 
material is placed in a press at this temperature and each block is 
subjected to a pressure of 120 tons. After leaving the press the 
blocks are gradually cooled in a water bath, and are then ready 
for use. 

In the earlier years of the industry blocks were made 4 x 5 x 12 
inches. A depth of 5 inches, however, was considered to be un- 
necessary, and the present practice makes them of the same dimen- 



22 ASPHALTS. [chap. ii. 

sions as above, except that the depth is 4 and 3 inches, the blocks 
weighing 13^2 and 18 lbs., respectively. These blocks are carried 
to the streets and laid upon a base of either gravel, broken stone, 
or concrete, as the case may be. The blocks are laid in practically 
the same manner as are bricks, the joints being filled with fine 
sand. 

Another form of asphalt blocks, known as the "J enner " pat- 
ent, is sometimes used, in which the broken stone is replaced by 
granulated cork. Such blocks were laid on Fifth Avenue, New 
York, between Thirty-fourth and Thirty-sixth streets, in strips ten 
feet wide, adjacent to the curb. The grade on these two blocks 
being somewhat steeper than the remainder of the avenue, it was 
deemed best to provide a better foothold for horses in slippery 
weather than the ordinary asphalt. The blocks are 2 x 4^ x 9 
inches, and were set flatwise. 

The courtyard of the Waldorf-Astoria was afterward laid 
with such blocks. This pavement was laid in the fall of 1897, and 
in the spring of 1900 was in very good condition. It cost $5.25 
per square yard, exclusive of foundation, under a fifteen-year 
guarantee. Although very desirable for driveways and bridges, 
«cork blocks can never be very generally used on account of their 
excessive cost. 

The question of patents has taken me from the subject of 
asphalts mastics to which I must return. For sidewalks or iron 
bridges asphalt coule is often used where the roadway is of asphalt 
pitch composition, or, as is known, the "Standard American Pave- 
ment," as being subject only to footwear on the top surface — need 
only be laid one inch thick, and here, as in other cases, where 
heavy steam rollers cannot well be used for compression, the mastic 
is preferable, as it is so solid when poured on the surface to be 
covered that it needs only a slight pressure from the workman 
spreading it to the required grade. 

The American rock asphalts have not proved satisfactory for 
the manufacture of mastic ; this is from the fact that they are 
generally of sand-rock and not lime-rock formation. A company 
in St. Louis tried the experiment of making a mastic from the 
Indian Territory asphalt sandstones, but I understand abandoned 
its use for that of European rock mastic. Another Western firm 
tried the use of Kentucky asphalt sandstone, but also changed to 
limestone. The single exception, I personally know of, is found in 



ROCK ASPHALT MASTIC. 



23 



the Texas rock asphalt mixed near Cline, in Uvalde Co., which is 
a genuine asphalt limestone. I visited these mines in the spring of 
1 90 1 and was much interested in the formation, which was shell 
limestone richly impregnated with bitumen, the average analysis 
showing 16 per cent, of bitumen with streaks much richer. I 
obtained very fine specimens of fossils showing different kinds of 
shells and proving that the mine had originally been under the 
ocean. This rock having been reduced to a powder is rich enough 
to be cooked into a mastic without the addition of bitumen, a small 
percentage of maltha, however, is desirable to cause it to flow 
readily into molds. At San Antonio a large stable in the rear of 
the "Menger" Hotel has a floor laid some years ago with this 
material which has stood the test of hard usage even better than 
the average European mastic. It has been laid also in Houston, 
Texas, to a considerable extent, but the heavy cost of freight 
prohibits its use in the East; New Orleans, however, may prove 
a favorable point for its use. 



Chapter III. 
TRINIDAD ASPHALT. 



TRINIDAD asphalt is the bitumen best known in the United 
States, and its use for street pavement has been colossal. 
This asphalt was first used as a substitute and improvement on coal 
tar for roofing and like purposes, and succeeded the coal tar pave- 
ments first brought into prominence in the "Tweed Ring" days. 

In 1870 Professor E. J. De Smedt, a Belgian chemist, laid 
what is believed to have been the first sheet asphalt pavement in 
this country in front of the City Hall in Newark, N. J. His Euro- 
pean knowledge led him to endeavor to make an artificial bitumin- 
ous mixture on the line, as far as possible, of the natural rock 
asphalt powder used in Paris. 

In 1873, Fifth Avenue, New York, opposite the Worth Monu- 
ment, was laid with this composition which was described as a 
mixture of properly selected sand and pulverized carbonate of 
lime cemented together by suitable asphalt, the latter being first 
refined and tempered with heavy petroleum oils or residuum. 

From these beginnings have evolved the immense industry 
of the "Standard Asphalt Pavement," of which to-day, there are 
forty million square yards in the United States, and of this quantity 
it is claimed 85 per cent, is of a mixture in which Trinidad asphalt 
is used. 

Municipalities and engineers have been greatly exercised over 
the question of the supposed difference in asphalt refined from 
the Pitch Lake and from adjoining properties. The writer has 
always maintained that there was no difference in the qualities and 
this is now the generally accepted decision of army engineer offi- 
cers and city engineers. 

The deposit of the Pitch Lake, as described by Mr. P. W. 
Henry, general manager of the Barber Asphalt Paving Co., occu- 
pies a bowl-like depression, probably the center of an extinct mud 
volcano, some of which are found in other parts of the island. 




'ASPHALTS' 



TRINIDAD ASPHALT. 25 

The center of the deposit is about three-quarters of a mile from 
the shores of the Gulf of Paria, and about 135 feet above the level 
of the sea, making it easier of access and simplifying the question 
of shipment. The surface is hard enough, except in irregular 
patches in the center, to bear the weight of carts and mules. It is 
necessary, however, for one to keep moving, otherwise he soon 
sinks in the material which, under the hot rays of the sun becomes 
quite mobile, although not sticky, owing to the large amount of 
water which it contains. The surface of the deposit is divided into 
irregular areas, from 60 to 150 feet in diameter, separated by 
crevices several feet across and from six inches to six feet or more 
in depth, in which rain water collects and in which fishes, some six 
inches long, resembling mullets, disport themselves. Each of these 
areas has a motion of its own from the center to the edge, due to 
the gas which is being evolved. If a stake is placed in the center 
of one of these areas it will gradually work to the edge and finally 
disappear. The crevices are found where the different areas meet, 
and although the edges of the asphalt in these areas touch each 
other at a greater or less depth, they do not appear to unite. 

This deposit has well been called a lake, and it possesses the 
qualifications which such a name would imply. It occupies limits 
well defined by shores. From borings made it appears that the 
deposit occupies a bowl-shaped basin, the bottom of which 100 feet 
from the shore is about 90 feet from the surface. The depth in 
the center is unknown as it was impossible with the implements 
employed to bore to a depth greater than 135 feet, through all of 
which the material was similar to that on the surface. 

When asphalt is dug from any portion of the deposit, in the 
course of a few days the hole is filled by new material coming from 
below, but the entire area of the lake, 114 acres, is lowered in con- 
sequence, showing that the mass acts as a liquid of less mobility, 
however, than water. 

The composition of the asphalt is of remarkable uniformity, 
no matter from which portion of the lake it is taken. Sam- 
ples taken 135 feet deep at the center did not differ in composition 
from those taken on the surface a few feet from the shore, show- 
ing the homogeneousness of the entire mass. Then, too, the sur- 
face is in constant motion. There are on the surface of the lake 
half a dozen or more islands, from 50 to 150 feet in diameter, com- 
posed of floating vegetation, with trees thirty to forty feet high 



26 ASPHALTS. [chap. hi. 

and dense undergrowth. From accurate surveys it was found that 
one of these islands in one year moved over 25 feet. There are 
also more rapid movements corresponding to currents and eddies 
in a lake. In making surveys for the tramway, different lines 
were run across the lake and stakes put in every 100 feet. These 
stakes were put in line with a transit, and the following day the 
alignment was about the worst possible. In 20 days one of the 
stakes had moved 24 feet, or over a foot per day, and other stakes 
from that amount down to a few feet. 

This motion is due to the evolution of gas which is constantly 
being given off, and in some places in such quantities that it can be 
ignited by a match. Then, too, the lake is fed by springs bringing 
in new material to the amount of at least 10,000 tons per year. 
Near the center of the lake this soft asphalt appears and spreads 
over the old and hardened surface. The lighter oils evaporate 
under the rays of the tropical sun and the new material then be- 
comes hardened like the rest of the lake. 

The resemblance of this deposit to a lake may therefore be 
summed up as follows : Its occurrence in a basin with well defined 
shores and bottom; its movement as a mass, preserving its level; 
the uniformity of its composition; the movement of its surface; the 
presence of islands and the existence of springs. 

From levels taken by Mr. Henry in February, 1893, and again 
a year later, it appears that the center of the lake is almost a foot 
higher than the edges. This is probably due to the ebullition of 
the soft asphalt near the center. Levels have been taken every 
year since that date, and it appears that the lake preserves its con- 
tour, although the general level has been lowered nearly four feet 
in the past eight years. It has been found that the removal of 
about 18,000 tons of asphalt will lower the level one inch, and as 
the output is about 100,000 tons per year, the level is lowered from 
five to six inches per year. 

From the borings, however, it is evident that for several gen- 
erations to come there will be no shortage. These borings were 
made with the ordinary portable water-jet machine, such as is used 
in making borings through sandy material, and it was well suited 
for the purpose. It took several days to make the borings in the 
center of the lake, and by that time the casing had gotten so far 
out of plumb, due to the motion of the asphalt, that it was impos- 
sible to drive it any deeper. This casing finally disappeared, 



TRINIDAD ASPHALT. 2 J 

although its top originally stood six or eight feet above the 
surface. 

The asphalt is dug by means of picks or mattocks just before 
dawn, when the asphalt is comparatively brittle, and in the early 
days of the industry was loaded upon carts and taken to the beach, 
where it was stored until the arrival of vessels, or dumped directly 
into lighters which carried it to the sailing vessels or steamers 
anchored half a mile out from shore. 

As the business increased it became necessary to install more 
rapid and economical methods of loading. Surveys for the tram- 
way and pier were made in February, 1893, by Mr. Henry, who 
outlined the plan finally adopted. Detailed plans and specifications 
were made by L. L. Buck, C. E., and the resident engineer in 
charge of erection was E. G. Freeman, C. E., and it was finished in 
the fall of 1894. 

In consequence of disputes and claims of inferiority of the 
so-called "Land Asphalt," Professor S. F. Peckham, in 1895, vis- 
ited Trinidad, and as the result of his investigations reported that 
he was ' 'quite at a loss to determine why Mr. Richardson alleges 
such a specific distinction between what he is pleased to term 'lake' 
and 'land' asphalt. It appears to me to be a distinction without a 
difference." 

Professor Peckham states that it is evident that for an indefi- 
nite period there has been an outflow of bitument from the lake 
towards the sea, at La Brea, not over its rim, but through a crevice 
in its side ; in fact, through its broken-down side ; and that, not- 
withstanding the vast quantities of asphalt now being taken from 
the lake by the concessionaires, the movement is still out of the 
lake. Captain Alexander, in 1832, spoke of the flow out of the lake 
as "immense." Manross, in 1855, says: "This stream of pitch 
has been dug through in several places, averaging from 15 to 18 
feet in depth. A well dug at one point on the slope of the over- 
flow, was abandoned still showing asphalt, at the depth of forty 
feet. Several village lots have ben excavated to a depth of twenty 
feet still in asphalt. The invariable reply of the negroes to the 
question: "Have you ever dug through the asphalt?" was, "No, 
sir." The conclusion that Professor Peckham reached on the 
ground was, that the asphalt flowing down the slope to the sea 
fills a ravine excavated by water, and that it is slowly moving out 
of the lake with the pressure of the asphalt in the lake behind it. 



28 ASPHALTS. [chap. in. 

This conclusion is in harmony with the testimony of observers 
for the last hundred years. It is from one of such overflow de- 
posits in the village of La Brea that the asphalt from the Countess 
Dundonald's property is obtained. The Roman Catholic Church 
property also has reduced large quantities of asphalt which has 
allowed of the competition in asphalt pavement work, which was 
so prominent a feature during 1899 to 1902. 

For paving purposes refined Trinidad asphalt of itself is too 
hard and brittle to form the cementing agent to bind the particles 
of sand together. It is therefore necessary to use a flux to bring 
the asphalt to the proper consistency. For this purpose petroleum 
residuum has been generally used, although liquid asphalts from 
California have been used to some extent and with more satisfac- 
tion. 

As liquid asphalt is more expensive and residuum has been 
used for many years with fair results, it has been the fluxing agent 
in general use. Professor Samuel P. Stadler, after exhaustive 
tests gave the opinion that oil residuum should not be used, and 
that maltha, of the nature of the California liquid asphalt, was the 
best flux. 




'A S P II A LTS' 



Chapter IV. 

PETROLEUM RESIDUUM AND CALIFORNIA MALTHAS 
AS A FLUXING MATERIAL. 



REFERRING to the use of petroleum residuum as a fluxing 
material, this residuum is a heavy, dark oil, resembling the 
cheaper lubricating oils, and contains none of the lighter oils. Its 
gravity is from 20 degrees to 22 degrees Beaume, flash point about 
450 degrees F., quick flow at 78 degrees F., and containing only a 
few per cent, of volatile matter in seven hours at 400 degrees F. 

In order to make a satisfactory asphalt cement (as the mix- 
ture of refined asphalt and residuum is called), it is customary to 
mix it in the proportion of about 100 parts of refined asphalt to 20 
parts of residuum. The asphalt is first melted in tanks and the 
residuum is then added and thoroughly mixed by agitating with 
air or steam. As the quality of the residuum varies, it is not pos- 
sible to gauge the exact amount necessary by weight. Samples 
are therefore taken by the foreman in charge and tested by chew- 
ing. By practice a man can become expert in this line, but it is of 
course necessary to have a standard sample for comparison. At 
the laboratory and at the larger plants the consistency of the 
asphalt cement is tested by an apparatus called the penetration 
machine, and the consistency of the cement is recorded. Other 
methods for determining the consistency are also in use, and each 
has its merits. For quick service the chewing test is as accurate 
as any other, but there is no method of recording its results. The 
asphalt cement, which in the tanks is carried at a temperature of 
300 degrees to 350 degrees F., is now ready for use, and is added 
to the hot sand and other mineral matter in a mixer which is simply 
a box encasing two shafts revolving in opposite directions, on 
which are blades shaped like propeller blades. The mixture is gen- 
erally made in batches of nine cubic feet, and the time of mixing 
is from a minute to a minute and a half. The resultant mixture is 



30 ASPHALTS. [chap. iv. 

then dumped into wagans, hauled to the street, raked and rolled 
with a steam roller, and the asphalt pavement after a few hours 
cooling, is then ready for traffic. 

In 1894 the Citizens Municipal Association and Trades 
League of Philadelphia employed Professor Samuel P. Stadler and 
Mr. J. Edward Whitfield to investigate the properties of the dif- 
ferent fluxing materials and they reported that "better, stronger 
and in all probability more durable paving composition can be 
made than those now being made with the aid of oil residuum." 
This decision was based on exhaustive tests of Trinidad with Cali- 
fornia and Utah Malthas. 

The general deduction was that the blending of the asphalt 
and the oil-residuum is an unsatisfactory one on the score of its 
lack of durability, and I have since found from conversation with 
practical men of many years' experience in asphalt paving that 
such is the common belief. It is also admitted by the chief writers 
on the subject of asphalt paving that the quality of an asphalt is 
reduced in the ratio of the percentage of increase of petroleum oil 
used. 

There are two methods as stated by Messrs. Stadler and 
Whitfield by which the use of petroleum residuum in asphalt 
paving mixtures can be done away with; the first is to find natural 
asphalts which retain sufficient of their original asphaltic oils to 
make it possible to use them with no other admixture than the 
proper amounts of sand and pulverized limestone, the other is to 
mix with the hard natural asphalts, liquid natural asphalts, of 
which a number are found on the Pacific Coast, and in Utah, 
Idaho, Montana and elsewhere in the West. 

The second method of making a paving composition which 
shall do away with the necessity for the use of the oil residuum is 
to flux the solid asphalt with the natural liquid asphalt. This has 
been done already in California with excellent results. 

As no figures had then been published by which one could 
judge of the reliability of these claims, it was determined to make 
a study of the paving compositions that could be made with the 
liquid asphalts used as tempering material for the solid asphalts. 
They therefore procured a quantity of California liquid asphalt and 
a specimen of liquid asphalt from Utah. In order to have a clear 
understanding of the nature of these materials and how their addi- 
tion would effect the composition of the finished mixture, it was 



PETROLEUM RESIDUUM. 31 

thought desirable to make a partial chemical analysis of them, de- 
termining the amount of bitumen contained and its quality. 

These analyses showed : California maltha 98.70 per cent, of 
bitumen, and in the Utah 76.15 per cent, of bitumen, both soluble 
in carbon disulphide. 

California asphalts in forms of Maltha Brea, and Stone or 
Rock asphalt are found in abundance in the Southern and South- 
ern Central counties of the State. They were known to and used 
by the native Indians for making their canoes watertight, and 
in some measure as a mortar for cementing together the stones 
of their rude buildings, unconsciously following the practice of the 
Babylonians more than 4,000 years ago. 

As Maltha, the bitumen oozes from orifices in the earth, 
called locally "Tar Springs." 

At Brea, this exuded Maltha lies in blanket form, usually in 
thin masses but sometimes in deep bodies filling up holes, chasms 
and ravines. Under the action of the sun's heat the soft Maltha 
has slowly thrown off its volatile elements, which with the action 
of the oxygen of the atmosphere has produced a more or less hard 
and brittle asphalt, more or less pure or mixed with earthy matter. 

As Stone or Rock asphalt it is found in many places in regu- 
lar, true fissure vein formation of very old geological age, the vola- 
tiles nearly eliminated from gases and from the rocks and earth 
surrounding and covering it. 

The Maltha, as issuing from the Tar Springs is usually very 
pure in bitumen. 

The Brea is less pure and very variable, according as it gath- 
ered much or little sand, gravel or soil in its progress of crawling 
under the sun's heat. 

The Rock Asphalts are also widely variable in bituminous pur- 
ity, according to the amount of earthy or fossil matter intruding 
into the bitumen while still viscous or even at its earlier stage of 
fluidity on its way up and through the earth fissures. 

In one or other of these forms these asphalts have been in use 
in increasing quantities since the advent of Americans in Cali- 
fornia, most largely for roofing, next for paving and for lining 
reservoirs and tanks, and to a large extent for coating water pipe 
and protecting it from rust, acid and alkalies. 

For paving, the Rock Asphalt has been quite largely used in 
the Pacific Ocean States and Territories, but paving material made 



32 ASPHALTS. [chap. iv. 

from Refined Maltha is now being more largely employed owing to 
the very high purity of the bitumen, enabling shipment to far dis- 
tant points with virtually no dead matter in its composition to pay 
freight and handling on. The following table, giving an analysis 
of a common type of these Refined Malthas, will illustrate this : 

Table III. 

REFINED MALTHA PAVING CEMENT. 

Water and volatiles 09% 

Loss at 212° Fahrenheit: 

Total bitumen 98.33% 

Ash (finely divided silicium) 1.58% 

100.00% 

Bitumen composed of petrolene 75.15% 

Bitumen composed of asphaltene 24.85% 

Specific gravity of the cement, 1,050. 

Considerable quantities have been shipped to states east of the 
Rocky Mountains, and the increase in demand has shown a rapid 
growth from year to year. Shipments via Panama and Cape Horn 
to Europe are increasing, and an active trade is beginning with 
Asiatic Pacific countries. A recent shipment of some 500 tons on 
account of a 5,000 ton order has been made to Australia. 

Several thousand tons are used annually for coating wharf 
piles which the asphalt effectually protects against Teredos and 
Limnoriae. 

Some ten years ago a civil engineer (Mr. Templer Tickell) in 
employ of the British Government at Singapore shipped a quantity 
of refined asphalt from California and applied it upon the timbers 
of bridges, docks and buildings to test its efficacy in resisting the 
depredations of the wood-eating ants, which range in great armies 
through the Straits Settlement and attack everything of wood, 
completely consuming heavy timbers. The asphalt resisted them 
perfectly. 

Applied to metal surfaces which in the very hot and very 
humid climate of Polynesia corrode to an extent unknown in cooler 
and drier climates, Mr. Tickell found the California asphalts a 
perfect protection. The use of California asphalts for street pave- 
ments in eastern cities is growing rapidly. 

Samples of them were recently submitted to Professor A. W. 
Dow by a Western Asphalt Company and resulted in the following 
analysis and report: 



c r 

x 3 

& > 

a" w 

| - 
p 

- ~ 



c > 

to 
£ > 



CO 



x 



ft E 

O - 

B o 
8= > 




'ASPHALTS' 



PETROLEUM RESIDUUM. 33 

Table IV. 
ANALYSIS OF CALIFORNIA ASPHALT. 

(D) 

Hard. (G) 

Bitumen. Maltha. 

Total bitumen soluble In carbon disulphide 99.10% 99.68% 

Organic matter not bitumen 0.54% 0.12% 

Silica and clay 0.36% 0.20% 

100.00% 100.00% 

"None of the samples were appreciably altered by being kept 
at 300 degrees for six hours in an open vessel. This paving ce- 
ment is of the right consistency to make a good paving. It is 
adhesive and elastic. It is not brittle at a low temperature, nor 
does it become too soft at a high atmospheric temperature. These 
samples are superior to any I have ever examined in physical prop- 
erties, and rank among the better asphalts for paving purposes. 
Your (D) Asphalt Paving Cement, by combining with your (G) 
Liquid Asphalt will produce a most splendid article." 



Chapter V. 
VENEZUELA ASPHALT. 

VENEZUELA asphalt is more widely known to the public 
through the serious law suits which have almost caused 
international complications than from its actual business produc- 
tions, and I might almost say that Venezuela is about as prolific in 
law cases as in bitumens, but there are certainly large deposits of 
the latter throughout the republic. 

The Bermudez Lake, which up to the present has really been 
the only important source of supply, is situated across the Gulf of 
Paria, about 105 miles due west of the Trinidad Pitch Lake, in the 
State of Bermudez, Venezuela. It lies in a straight line about 20 
miles from the gulf, but by the San Juan and Guanoco Rivers the 
distance from the bar at the mouth of the river is some 40 miles. 

The San Juan is a deep, wide river and although there are 
only 19 to 20 feet of water at the bar, in the river itself, the water 
is in many places over 100 feet deep. From the San Juan branches 
a smaller river, the Guanoco, and three miles from the junction ts 
located the wharf along which steamers drawing 18 feet of water 
can lie and receive the asphalt. This wharf is located about five 
miles from the asphalt lake, to which it is joined by a narrow- 
gauge steam railroad. The lake covers an area of about 1,000 
acres, being nine times the area of the Trinidad lake. 

This larger area does not necessarily indicate a larger amount 
of material in the deposit, for the asphalt in many places is only 2 
to 10 feet deep. There are many springs of soft asphalt or maltha, 
the largest being about seven acres in area. Outside of the springs 
where new material is constantly exuding, the surface of the lake 
is covered with vegetation and trees, which must first be cut off 
to reach the asphalt. 

The quality of the asphalt varies from the maltha, or liquid 
asphalt, exuding from the springs to the hard glance pitch which 
has been produced by fires which during the dry season sometimes 



VENEZUELA ASPHALT. 35 

sweep across the lake. Underneath the roots of vegetation is the 
asphalt of commerce, which is handled in much the same way as 
Trinidad, although it is considerably softer. 

Its composition also differs considerably from that of Trini- 
dad, and the crude material does not present the uniformity of 
Trinidad. The crude Bermudez asphalt contains water, but it is 
present as a mixture and not as an emulsion. In percentage the 
water varies from 10 to 4 per cent., averaging 31 per cent., whereas 
in Trinidad asphalt the quantity is constant at 28 per cent. The 
mineral matter also varies from less than 1 per cent, to more than 
3 per cent., while the organic matter, not bitumen, varies from 1 to 
6 per cent. 

An average analysis of the crude material from the lake is as 
follows : 

Bitumen 66 per cent. 

Water 31 per cent. 

Mineral matter 1 per cent. 

Organic matter, not bitumen 2 per cent. 

In this case, as with Trinidad asphalt, the only element to be 
eliminated is water, and this is done in the same manner. 

The asphalt, although considerably softer than Trinidad, is 
dug in a similar manner and loaded into small side-dump cars run- 
ning on a portable track. These cars are pushed by hand to the 
terminal station on the shore of the lake, where they are dumped 
into boxes contained on flat cars. These cars are then taken by the 
locomotive to the wharf on the Guanoco River, about five miles 
distant, and dumped directly into the vessel, if one is alongside, 
otherwise they are dumped on the shore of the river, where there is 
considerable storage place. 

As the material is softer than Trinidad asphalt it is necessary 
to have the hold of the steamer or sailing vessel divided into com- 
partments in order that the material may not move too freely. If 
this were not done, the sailing vessel would get such a list in sail- 
ing for any length on one tack that it would be impossible to 
get her on the other tack, and the vessel would finally capsize. 
This same difficulty to a less extent would also occur in steamers 
where no provision for bulkheads was made. There is now at the 
Bermudez lake a refining plant. 

The first pavement laid with this material was on Woodward 
Avenue, Detroit, in 1892. Since then, it has come into general use 



36 ASPHALTS. [chap. v. 

in different cities of the country. When refined, the asphalt con- 
tains of bitumen 97.22 per cent.; mineral matter, 1.50, and organic 
matter, 1.28. The bitumen is composed of petrolene 77.90 and 
•asphaltene 22.10 per cent. The specific gravity is 1.08. The Ber- 
mudez asphalt has also found great favor from civil engineers, and 
large quantities have been used in reservoirs and other large con- 
struction work; the largest contract calling for its use is in the 
Rapid Transit Tunnel in New York, where all walls in contact with 
the earth were waterproofed with felt and the Venezuela bitumen. 
Prom Perdenales some shipments have been made and at Mara- 
caibo a large refinery has just been erected. 

It has been thought by some scientists that all the Trinidad 
and Venezuela asphalts have a common origin in volcanic erup- 
tions in the Gulf of Paria. 

Since the publication of the article on Trinidad asphalt there 
has been received a copy of a most interesting report on the Pitch 
Lake and its surroundings submitted to the Governor of Trinidad 
by acting Surveyor-General, Edmonstone Hodgkinson, under date 
of January 14, 1824. After three-quarters of a century the state- 
ments of his impressions have been verified, and his views are an 
interesting addendum to the literature on the subject. 

He stated that the Lake is situated upon the top of a ridge, 
about 25 or 30 feet above the level of the sea, from which there 
is a fall at three sides, on the North and West towards the sea, and 
on the East towards the interior of the country. It is principally 
towards the North that the Lake empties itself into the sea (if the 
expression may be used of that which has no sensible motion), but 
the formation of the stream, of pitch from the lake to the sea, a 
distance of about a mile and a half, is too apparent from the fact, 
to be mistaken. 

The pitch which the lake presents to the view is by no means 
the whole the district furnishes, the lake is merely the part over 
which the soil has not spread, so as to permit the growth of grass 
and wood on it, but there is a vast quantity of pitch from it, de- 
tached in portions, particularly to the northward up to and upon 
the seashore, and to the westward upon the estate of the late 
Madame Boussac, now held by Messrs. Montrichard, Labastide 
and Saubot. 

The different qualities of pitch observed are three in number, 
of which two may be said to be inexhaustible, the deficiency of any 




'ASPHALTS' 



VENEZUELA ASPHALT. 37 

that is taken away being quickly supplied by reproduction. These 
are the pitch of the lake and the liquid pitch found on the lot of 
M. Saubot, on both of which the volcanoes and the matter rising 
to the surface from them are distinctly visible. The liquid pitch 
found is in detached spots, sometimes near to and sometimes at 
some hundreds of yards distant from each other upon the land of 
M. Saubot, and the land called Ozon's, now also belonging to M. 
Saubot. These spots which are said to be about twenty, and of 
which ten or twelve were visited, are circular, of about 30 feet in 
diameter, with the volcano in the center from which a bubble like 
that of boiling water rises and bursts about every minute. The 
pitch is so nearly liquid that the specimen brought up was raised 
with a stick and let to run from it into a narrow-mouthed jar at 
8 o'clock in the morning with the thermometer at 79 degrees. 

The nearer to the volcano that the pitch is taken the more 
liquid it is, being then about the consistence of tar when prepared 
for use on board ship, but this liquidity ceases on its removal, 
although it is restored by exposure to the sun in this climate. The 
third sort of pitch differs in the external appearance from both the 
foregoing; it is neither liquid like that last spoken of, nor in a 
mass like that of the lake, but it is found under the surface and in 
the immediate vicinity of the liquid volcanoes in dumps or blocks 
about the usual size of pieces of sea-coal taken out with the soil, 
so loose that they may be taken out with a cutlass or any instru- 
ment sufficiently strong to remove the earth. This pitch, when the 
earth is washed off, appears blacker than that of the end of the lake. 
It may be that it was visible, for the spots which contain earth are 
not found in contact. On the contrary the liquid pitch abounds 
upon the land .of Saubot, nearer the lake, and the latter is mostly 
found further off and upon the land called Ozon's. 

If the pitch in blocks exists to any considerable depth — which 
there is no reason to disbelieve, but which fact is known — there 
will be found sufficient for almost any purpose, but it cannot be 
called inexhaustible with the confidence applicable to the other 
kinds, because its reproduction is not visible. 

Common experiments for fathoming the volcanoes have been 
tried in vain — large sticks 60 feet long have been swallowed per- 
pendicularly in the course of a few hours. A line would not an- 
swer the purpose, because it could not be redrawn. Mules and 
oxen have been frequently lost on them. 



38 ASPHALTS. [chap. v. 

Reverting to the lake and to the assertion that it empties itself 
into the sea, it may be observed that the whole natural savannah of 
La Brea, abou a mile and a half in length and about a quarter of a 
mile in width, is entirely pitch over which, except that part which 
is kept clear for the road, the soil has contrived to spread a thin 
covering of itself upon which the fox-tail and other coarse grasses 
grow. And this savannah is evidently the stream by which the 
pitch of the lake is emptied into the sea, however long the time 
may be that its passage occupies ; but that there is a motion is cer- 
tain, both by the houses in the village of La Brea on the seashore, 
which are sometimes raised a foot or two more at one end than 
the other, continue so for a year then the road which is annually 
made from the lake to the village by cutting out the watercourses 
with hatchets, is again filled with pitch before the return of the 
period. 

A fourth sample of pitch has been brought up, being that 
found at the village on the seashore. The intention of this is that 
it may be ascertained whether the pitch has deteriorated in quality 
in its passage from the lake to the sea, as if it has not, it may be 
cut out on the seashore at the very prow of the boat that would 
take it and the carriage from the lake w T Ould be saved. 

There is a bar off Point La Brea, but the anchorage for ship- 
ping is good inside. Off the shore the pitch under the sand has 
made the water shallower than it would otherwise be. 



Chapter VI. 
CUBAN ASPHALT. 

THE Cuban asphalt industry has not yet been fully developed, 
but recently has been brought prominently to notice in 
consequence of a report prepared for the U. S. Government by 
Mr. T. Wayland Vaughan at request of General Leonard Wood. 
It will be readily understood that during the Cuban revolution 
nothing was done in the way of working deposits, but prior to 
that period, some fifteen years ago, attempts had been made to 
utilize the Cuban asphalt for street pavements; there was a project 
to mix the asphalt with clay and other ingredients, but no success- 
ful results were obtained, and work attempted at Washington 
proved a failure. 

At the World's Fair in Chicago some may remember the solid 
block of asphaltum weighing 1,024 pounds, which was exhibited by 
Mr. Otto D. Droop, and which was analyzed by M. Leon Malo as 

Pure bitumen 70.00 per cent. 

Foreign matter 24.50 per cent. 

Water 5.50 per cent. 



100.00 per cent. 

This came from the asphalt mine known as "Angela Elmira," 
which is located about five miles from the town Bejucal in the 
Province of Habana, and which was then owned by the West 
Indies Co. 

The present owners made their first shipment to the United 
States in January, 1901, and brought their material before the Dis- 
trict of Columbia authorities in a practical way by demonstrating 
that a good paving mixture could be obtained by the blending of 
the material with a pure California liquid asphalt. 

Professor Dow in his last official report said of the sample of 
crude asphalt from the "Angela Elmira" mine and a sample of 
California maltha : "A proper combination of this asphalt and flux 
produce a cement that from all indications will rank among the 
best for paving," and portions of two streets in Washington were 



4 o ASPHALTS. [chap. vi. 

last year laid with this mixture. This material, which is a hard 
asphalt, is of course applicable to many purposes other than that 
of paving. 

Mr. Vaughan in his report says that the occurrence of mineral 
pitch or asphalt in the Island of Cuba has been known since the 
time of the Conquest. In the "General History of the Antilles," 
by Oviedo, published in 1535, mention is made of a spring of pitch 
near the coast in the Province of Puerto Principe. 

This material was used with an admixture of grease for paint- 
ing the hulls of vessels. The same author mentions the occurrence 
of pitch upon the shores of Habana Bay, where it was also used for 
a similar purpose. The presence of this mineral was noted . by 
Humboldt, who visited the islands in 1803, and it was mentioned 
both in the personal narrative of his voyage and in his essay upon 
the Island of Cuba. It is probable that Humboldt visited some of 
the localities which have since become prominent as asphalt mines 
in the vicinity of Habana. He reports that it occurs in the serpen- 
tine rocks in the form of fissure veins. He observed also some 
fluid bituminous material of the nature of petroleum running out 
of fissures in the same rock. 

In 1828 La Sagra, published in "Anales de Ciencias, Agricul- 
tra, Comercio y Artes," a journal formerly printed in Habana, a 
somewhat extended account of the occurrence of asphalt in the 
vicinity of Habana. Reference has also been found to a memoir 
on the bituminous deposits by one Navarro, published in 1829, and 
another by Moisant, in 1857, entitled "Memoria sobre los Produc- 
tos Bitumenosos de la Isla de Cuba." There is no question that 
asphalt is to be found in every Province in Cuba, but its commer- 
cial worth, as stated by Mr. Vaughan, should be carefully consid- 
ered before large investments for developing are made by capi- 
talists. 

Cuban maltha has been imported in some quantities for mixing 
purposes. Of this quality of bitumen, Mr. J. L. Hance, in a con- 
sular report, says near what was formerly the town of Sabanillo de 
la Palma, about 30 miles east of Cardenas and some four miles 
west of Hato Nuevo, on the north side of the railroad, is the well 
of J. B. Hamel. This well is sunk to a depth of about 80 feet in 
serpentine rock, and into it oozes a thick mineral tar. 

The material is drawn out by hand power, bucket and windlass 
being used. The output is about 20 barrels per day. In the vicin- 




'ASPHALTS' 



CUBAN ASPHALTS. 41 

ity of this well are two others, one about 300 feet further east and 
the other about 600 feet to the west. The mode of occurrence of 
the mineral is the same. No area of limestone was discovered 
associated with the asphalt, but fragments were struck in the well. 

About a mile southwest of Mina Hamel and about 300 feet 
north of the railroad is another area of natural tar wells or springs ; 
one well is said to be 60 feet deep. Maltha has exuded from it 
over a considerable portion of the immediately surrounding sur- 
face. The area of mineral tar occurs within a shallow topographic 
basin. There are hills occurring on both the north and south sides 
rising to 75 or 100 feet above the included depression. 

The elevation at Mina Hamel is probably not more than 25 or 
30 feet. One hole in this vicinity, according to H. E. Peckham, 
was fired during the last insurrection and burned for four months 
until a heavy rain finally put it out. At present the ground for 
70 or 80 feet around this hole is covered with coke. The well itself 
is full of rain water upon which float masses of vegetation 
stuck together with bitumen that comes from below. A pole 
pushed down into the water 8 or 9 feet meets resistance in a soft, 
yielding material, and if this can be brought to the surface it will 
be seen to be the same as that in the neighborhood. 

In Mr. Hance's account of the submarine deposits of asphalt 
from the Bay of Cardenas he says : "The deposits in the bay from 
which asphalt has been taken are four in number and of two 
grades. No. 1 is in the western part of the bay and produces a 
very fine grade of practically pure asphalt, used in the United 
States for the manufacture of varnish. 

I have myself seen a serviceable varnish made by the simple 
process of dissolving this quality of asphalt in turpentine. Asphalt 
has been taken from this deposit in large quantities for the last 21 
years. Recently, however, the work has not made rapid progress, 
owing to the frequent caving in of the sides of the shaft. 

The mode of operation is almost primitive. A lighter is 
moored over the shaft, which is from 80 to 125 feet in depth — 
varying according to the rapidity with which the asphalt is re- 
moved and replenished. A long iron bar with a pointed end is 
raised by a winch on board the lighter and allowed to fall, so that 
its own weight detaches portions of the asphalt, which is about as 
friable as cannel coal, and has much of its appearance. The gloss, 
however, is more brilliant. After a sufficient quantity has been de- 



42 ASPHALTS. [chap. VI. 

tached, a common scoop-net is sent down and filled by a diver — not 
in a diving suit." 

Mr. William Palmer, of the United States National Museum, 
says that of the asphalts in the Province of Pinar del Rio, the mines 
entitled Rodas Concepcion and Magdalena, belonging to Don Ra- 
mon Balsinde, as well as the sugar plantations, Canas and Toma- 
sita, on which these are located, are at the head of the extensive 
Bay of Mariel. These are mines worked under the open sky, 
upon masses of asphalt, notable for their dimensions, especially 
the mine Magdalena in plantation Tomasita, which measures in 
the part already laid bare by the works, 12 meters of thickness 
and more than 100 in length. This mass lies in the direction of 
west-southwest to east-northeast, and is probably a continuation 
of the other two mines situated on the neighboring plantation 
of Canas. 

Mr. Wm. Palmer says that on the rough exposed surface of 
the reef at Mariel there are patches of asphaltum from 1 inch co 
6 or 8 inches in diameter and rarely more than x / 2 inch thick. They 
occur always in the higher portion of the rock between cavities, 
and appear to have been drawn out by the heat of the sun. 

One mile south of Mariel Bay is a deposit of asphaltum which 
has been quarried to a depth of about 50 feet. Several wagon 
loads were taken to the barracks at Guanajay. It is barely possible 
that this locality corresponds to one of the two mines above de- 
scribed. Mr. Palmer states that there are other occurrences of 
asphalt eight or ten miles to the southwest. 

Near the town of Banes, between Mariel and Habana, are two 
other mines, known as San Jose and Constancia, which are the 
property of Mr. Henry L. Cranford. These mines have never been 
worked extensively, and, according to Salterain, the production 
scarcely reached 400 tons during the two years preceding 1883. 

In the Province of Matanzas, nine or ten miles northwest of 
Matanzas ,about one mile east of north of the property known as 
El Recro, now owned by Captain L. H. Mattair, U. S. A., there 
is an occurrence of asphalt on the north side of a hill. The asphalt 
oozes out in liquid form and impregnates the surface sands and 
gravel, cemeting them into a kind of a pudding-stone. It also 
accumulates in small quantities in ditches which have been dug 
here for the purpose of testing the yield. 

There is no great amount of the asphalt escaping to the sur- 



CUBAN ASPHALTS. 43 

face, although the yield might be materially increased by sinking 
a shaft on the fissure. It exudes apparently from small fissures in 
the serpentine near its contact with a hard limestone, the serpen- 
tine forming the hill above and the limestone lying on its lower 
flank. The latter rock has no perceptible odor of asphalt or 
petroleum, and therefore probably has no association with the 
origin of the bituminous material. 

Another reported occurrence of asphalt is in the vicinity :>f 
Guamacaro, between the towns of Limonar and Cardenas. 



Chapter VII. 
AMERICAN BITUMINOUS LIMESTONE. 

AMERICAN natural bituminous limestone has been before 
referred to as found in Uvalde County, Texas. In a recent 
report formulated for the United States Bureau of Geological Sur- 
vey of the Department of the Interior, Mr. George H. Eldridge 
states that the only deposit worked in this somewhat extensive 
field is that by the Uvalde Asphalt Company, eighteen miles west 
of Uvalde, and eight miles southeast of Cline, a station on the 
Southern Pacific Railroad, with which it is connected by rail. 

The limestone quarried primarily consists of what seems to 
be an assemblage of minute organisms, together with a conspicu- 
ous proportion of crystalline calcite. Molluscan remains, often of 
large size, are also present. Through the mass of the rock there 
is a high per cent, of interstitial space, which in some instances 
may even exceed the solid portions. In addition to the interstitial 
space, properly so-called, are cavities produced by the removal 
of the molluscan remains and other of vug like character. 

These spaces, institial and other, are occupied by bitumen, but 
it is evident by the many examples throughout the bed that the 
supply was inadequate to completely fill the intervals provided, 
or that the channels to the same were blocked before the filling 
was accomplished. An interesting feature in connection with the 
larger cavities of the rock is the presence of white, well-crystallized 
calcite, which has replaced the shells of the molluscan forms orig- 
inally present, and has also been deposited in secondary form on 
the walls of the cavities, whether of animal origin or vugs. The 
bitumen, in passing into these cavities, has filled, in instances, every 
angle made by the crystalline lining of the walls, and fractures of 
the rock now yield most beautiful cross-sections. 

The asphalt itself has a brilliant luster when fractured, but 
when, in the broken rock, that portion which formerly was in 
contact with the walls of the cavities it filled is exposed, the bril- 







'ASP HALTS' 



AMERICAN BITUMINOUS LIMESTONE. 45 

liant luster is wanting, a surface of dead black replacing it. The 
material is brittle, and in hardening apparently suffered no shrink- 
age. The asphaltic limestone itself is tough and unyielding. 

Throughout the rock occasional particles of pyrite are ob- 
served, and there are instances in which both these and calcite 
have been caught up and carried on in the flow of the infiltrating 
asphalt. The molluscan cavities are varied in form and size, and 
embrace those of both bivales and univalves. Among the former 
is one resembling a Gryphaea ; among the latter, a long, tubular 
form showing delicate striations on its surface. This especially 
abounds. 

A feature of the bed is the presence of small gray to white 
bodies of calcite of such close texture that they remained unim- 
pregnated by the bitumen. Such bodies are excessively hard, are 
lacking in interstitial spaces, and even have the tubes which they, 
too, carry filled with secondary, earthy and crystalline calcite. In 
the northern part of the quarry, rock of this composition and 
texture may equal the more porous, bitumen-bearing portion, im- 
parting to the bed a marbleized and mottled effect. 

In this portion of the quarry there is also a transverse or 
vertical joint plane, which is of interest chiefly because of the 
impoverishment that has taken place in the bed on either side 
— on the north to a distance of 8 inches to 1 foot, on the south 
less. The line between the impoverished and rich portions, as 
exhibited by their brown and black colors, respectively, is, too, 
quite as distinct as the joint plane and practically parallel with it 
throughout. 

The amount of bitumen in the rock of this quarry is said to 
vary between 10 and 20 per cent., 14 and 15 being common, while 
20 occurred in one locality in a body of considerable proportions. 
The structure of the rock has naturally had a most material in- 
fluence upon the distribution of the bitumen. 

The extent of the enriched body of limestone at the Uvalde 
Company's quarry had not been determined either laterally or in 
depth, but it could be easily and economically ascertained with a 
drill, for the position of the bed is at most but a short distance from 
the surface. The outcrop of the limestone shows it, however, to 
have been more or less impregnated, and doubtless with important 
interruptions, throughout an area of several miles. 

The area of rock removed at this quarry, though somewhat 



46 ASPHALTS. [chap. vii. 

irregular, is between 300 and 400 feet in diameter, while the depth 
quarried averages perhaps 15 feet, the enriched rock below this 
passing beneath water level. The section of limestone exposed is: 
At the top, 3 or 4 feet of barren, drab, or buff rock of the composi- 
tion described as general for the unimpregnated portions of the 
bed, this everywhere forming the cap; beneath this, a zone 1 or 2 
feet thick of impoverished brown rock, breaking more easily than 
the richer portions below; finally, the bitumen bearing bed of high 
per cent., 18 feet in full depth to the floor of the pit. 

The material from this mine has been used for about 200,000 
square yards of street pavement in the cities of San Antonio, Hous- 
ton, Shreveport, Waco and Palestine, Texas. The heavy freight 
has prohibited its use in Eastern cities. 

The specifications for this asphalt as drawn up by Mr. E. G. 
Truehart, City Engineer of San Antonio, calls for the natural rock 
asphalt to contain from 12 to 14 per cent, of natural bitumen, 80 
to 88 per cent, of pure bicarbonate of lime, and must be free from 
quartz, sulphates, iron pyrites or aluminum. 

The rock is first crushed and reduced to a powder, after which 
it must be heated in a revolving cylinder from 250 degrees to 320 
degrees Fahrenheit, depending on the time of year and distance to 
be hauled. Nothing whatever shall be added to or taken from the 
powder obtained by grinding the bituminous rocks. No binder will 
be required if this material is used, but care must be taken to leave 
the top surface of the concrete of sufficient roughness to obtain a 
good bond. 

The powder must be carefully leveled and spread in one con- 
tinuous sheet in such a manner that it will be 2 inches in thickness 
after compression. It must be hot when spread, and therefore, if 
so ordered by the engineer, it shall be brought to the street in 
boxes that can be handled by two men and dumped at the exact 
place where it is to be spread. The tamping must begin imme- 
diately after the spreading of the powder, at first carefully, and then 
gradually augmenting the force with tools made especially for the 
purpose, heated to the proper temperature in portable furnaces. 

The entire surface must be thoroughly tamped with hand 
tampers and then gone over with smoothing irons, till it presents a 
glossy appearance. Dry hydraulic cement will then be swept over 
the top, and the surface rolled with a steam roller weighing no less 
than six tons. The rolling will be first done longitudinally and then 



AMERICAN BITUMINOUS LIMESTONE. 47 

transversely at an angle of 45 degrees from both sides of the street, 
and continued until the pavement has been thoroughly compressed. 

Great care must be exercised in making a proper bond with 
the surface, which has been already laid and allowed to cool. First 
all loose and all uncompressed powder must be removed from the 
edges of the pavement and the joints swept perfectly clean. 

A gasoline heater must then be used in heating thoroughly the 
rough edges of the pavement already laid, before new material is 
added; the spreading, tamping and rolling then goes on as before, 
the end intended being to leave no trace of the junction. If so 
ordered instead of applying the material to the rough edge, the 
said edge shall be cut with an axe so as to leave a clean smooth 
joint ; this joint must then be well painted with a coating of asphaltic 
cement before the heated powder is laid against it. 

Bituminous limestones are also found in Indian Territory, but 
of very imperfect impregnation. Of that in the Buckhorn district 
Mr. Eldridge reports that the rock of the quarry is very massive, 
with a texture varying between earthy, granular and crystalline. 
The crystalline texture is the most prevalent in the upper half of 
the deposit, the earthy and granular in the lower half. The aver- 
age per cent, of bitumen in the quarried rock is between 5 and 6, 
based on samples from the stock piles. 

Different portions of the bed, however, vary somewhat in rich- 
ness, that quarried, which is the granular crystalline, being regarded 
as the most satisfactory. The color is a deep chocolate brown in the 
more homogeneous, granular, and finely crystalline portions, vary- 
ing to brownish gray in those more coarsely crystalline; the first 
described is the richer in bitumen. 

The rock is stratified, but the bedding is extremely heavy in the 
lower middle portion. Near the top and bottom the beds are from 
2 to 10 feet thick, and the divisional planes are especially pro- 
nounced. Bodies of highly crystalline calcite are irregularly but 
profusely distributed through the upper third of the mass, and in 
their poverty in bitumen are in marked contrast to the general 
rock of the quarry. 

About 70 feet from the top of the limestone is a narrow belt in 
which blue translucent chert abounds, and there is a trace of chert 
also at the base of the bed. 

In the lower portion of the mass as quarried is a zone, about 
20 feet in width, that presents the aspect of having originally been 



48 ASPHALTS. [chap. VII. 

laid down as a calcareous mud. It is of a browner color than the 
crystalline granular rock, and is regarded of slightly lower value. 

In this connection it may be noted that there are many instances 
of muddy texture in the limestones throughout the Buckhorn dis- 
trict, which, coupled with other features, are suggestive of a sedi- 
mentary origin for the greater number if not for all of them. 

The effect of the calcite bodies in the upper portion of the lime- 
stone upon impregnation is noteworthy, the universally close union 
of their crystals preventing infiltration into their substance of more 
than the merest trace of bitumen, and often none whatever. In the 
portion of the limestone surrounding these bodies, however, infiltra- 
tion has been free, or at least in proportion to the absence of the 
calcite structure. 

In the Brunswick district there is a quarry of very similar for- 
mation, the earthy, granular, and crystalline texture are all re- 
peated ; the barren calcite bodies are present, in equal contrast with 
the general mass of the rock; the calcareous is as readily identified 
in one locality as in the other, and each variety of rock in texture 
shows the same difference in the degree of impregnation. 

If there be a difference in the rocks of the two localities it is 
in an apparently more general distribution of the calcite bodies 
through the rock of the Brunswick quarry and a possible slight 
lowering in consequence, of an otherwise equally maintained aver- 
age in the bitumen percentage. 

A feature, too, conspicuous in certain portions of the Bruns- 
wick pit, is the filling of fracture cracks with pure bitumen, derived, 
probably, by infiltration from the main body of the rock. This rock 
has been used for the manufacture of asphalt Mastic which has been 
laid extensively in Western cities for brewery floors. 



of O 




"ASPHALTS' 



Chapter VIII. 
BITUMINOUS ASPHALT SANDSTONE ROCK. 

NATURAL bituminous asphalt sandstone rock as in contradis- 
tinction to limestone, appears to be peculiarly of American 
origin. It is found in Kentucky, Missouri, Indian Territory, Texas, 
Utah and California. 

The difference between the limestone and sandstone bituminous 
impregnation appears to be most marked, it is seen that the bitumen 
softens the limestone and is homogeneous, whereas the bitumen 
with the sand remain two distinct substances although they can be 
compressed into a compact mass when heated. 

The most important fields operated are those in Kentucky and 
a quantity of pavement has been laid with the sandstone in Louis- 
ville. Professor Eldridge says that bitumens in Kentucky occur as 
impregnations of sandstones. They are, perhaps the result of ex- 
posure in outcrop of oil-bearing strata, the petroleum having thus 
been converted by loss of the lighter hydro-carbons and by oxida- 
tion into a product of asphaltic nature. 

The sandstones thus impregnated carry in freshly picked faces 
of the quarries from 4^ to 7^ per cent, of bitumen, amounts that 
would, perhaps show material increase at a distance from the ex- 
posed surfaces. The horizons at which the bitumens occur include 
the conglomerate at the base of the coal measures, a sandstone a 
little above, and the several sandstones of the Chester series of the 
lower carboniferous. The enriched beds are met in outcrop in many 
localities in Breckenridge, Grayson, Edmonson, Warren and Logan 
counties. 

In Breckenridge county, The Breckenridge Asphalt Co. has 
opened two quarries about 100 yards apart, near the point of the 
ridge between the forks of Lost Run, two miles south of Garfield. 



50 ASPHALTS. [chap. viii. 

Each is about 200 feet in diameter and shows practically the same 
section of sandstone, and variation in thickness or in the degree of 
impregnation being such as may be expected betwen different points 
in the same bed. 

The sandstone is of sharp, fine-grained quartz. Of the 14 feet 
enriched, the lower 7 or 8 are said to carry an average of 8 per 
cent, (varying between 6 and 10) of bitumen and constitute the 
shipping rock. The sample collected by Professor Eldridge con- 
tained a little less than 6 per cent. Above this the amount of bitu- 
men is considerably diminished and with exceptions the rock is 
treated as refuse. There is no distinct line of demarcation be- 
tween the richer and poorer horizons, a wavy zone of gradation 2 
or 3 feet in width existing between the two. This zone affords a 
certain amount of second grade rock, to which is occasionally 
added material of equally low per cent, that may chance to occur 
in the underlying portion of the bed. This second grade rock is 
then occasionally made available by thoroughly mixing it with 
the highest grade from the mine. 

A feature of interest — not only in the Breckenridge quarries 
but in all visited — is the impoverishment that takes palce for 6 or 
8 inches on either side of joint planes. Beyond this the rock 
maintains its average bitumen contents. 

In Grayson county exploitation has been made by Schillinger 
Bros, and Dr. Wilham F. Breyfogle. One of the Schillingers' 
mines at Black Rock produces a rock which is a medium-grained 
massive sandstone, of a thickness of 8 or 10 feet, the lower 5 of 
which is impregnated with bitumen to an average of perhaps 6 
per cent, distributed in greater proportion through the lower 3 
feet of the mass. Of the Breyfogle quarry near Tar Hill Pro- 
fessor Eldridge reports that the rock is a sandstone composed of 
medium to coarse grains of quarty, much coarser, as a rule, than 
the material of the Leitchfield flag. The latter rock is also gen- 
erally thin bedded, hard, and durable, and makes an excellent 
flagging, all in marked contrast to the features of the Big Clifty 
sandstone. 

The impregnated zone at the Breyfogle quarry, embraces a 
thickness of about 10 feet in the upper portion of the Big Clifty 
sandstone. Of this the lower 5 or 6 feet are of sepecial richness 
carrying a somewhat variable amount of bitumen, indeed, but, per- 
haps, an average of 7 per cent. Upon passing under greater cover 



BITUMINOUS ASPHALT SANDSTONE ROCK. 51 

it is quite possible that the upper portion of the zone will show an 
increase in its contents. 

Between the two portions there is no definite line of division. 
An incidental feature at this quarry is the heavy cross bedding, 
irrespective of which, however, the bitumen appears to have im- 
pregnated the rock to a general level, thus making productive at 
one point a layer that is apparently unproductive at another. An- 
other feature is the degree in which the bitumen seeps from the 
exposed faces of the quarry, even from levels in the sandstone 
where there are no visible division planes. 

Where crevices, either natural or formed by blasting, have 
remained open, such seepage becomes of added interest as a pos- 
sible suggestion regarding the formation of gilsonite and other 
veins of related material. The bitumen, always of a highly gummy 
consistency after leaving its bed, is seen slowly trickling from the 
sides of the crevice, deposting one layer over another, yet the 
several layers blend in a homogeneous mass but a short time after 
the flows. Held in the bitumen, also, are small rock fragments 
that have tumbled into the crevice and have been taken up by the 
slowly flowing mass. Such material is now hard, even semi-brittle 
in instances. 

In Edmonson county the geological horizon of the bituminous 
sandstone of the Bee Spring region was traced by Mr. S. D. Averitt 
from Leitchfield, 15 miles north. The same succession of beds is 
encountered in this section as in the region of the Schillinger No. 
2 Prospect, but in more extended order. The roofing limestone of 
the Chester appears at Harold Hill, 5 miles south of Leitchfield. 
It is here about 6^ feet thick and rests upon 6 to 8 inches of marl. 
It has the same lithological and paleontologic characters as in 
other places in western Kentucky. 

There are many deposits of bituminous sandstone in this part 
of Edmonson county, and in many places small tar springs, rather 
than saturated sandstone, are found. One deposit of consider- 
able extent is found 2 miles northeast of Bee Spring, on the farm 
of Mr. J. Meredith, and another i l / 2 miles south of Bee Spring. 
None of the deposits are worked and their value is undetermined. 

The deposits already described are found along the eastern 
border of the coal measures ; those that follow occur along the 
southern edge of this area. The deposits of bituminous sandstone 
in Warren county are confined to its extreme northern end, the 



52 ASPHALTS. [chap. VIII. 

lower coal measure — Chester terrane entering it only to a limited 
extent. But two quarries are opened within the county, neither, 
however, more than a prospect. 

They are located on what is known as the Cherry Farm, at 
Youngs Ferry, on Green River, 12 miles north of Bowling Green. 

Two openings, about 300 yards apart, have been made in the 
bituminous deposits of this locality. One, the eastern, near the 
summit of the ridge, is being developed by the Green River As- 
phalt Co. ; the other, the western, is controlled by the Sicilian As- 
phalt Company, but has remained idle since the shipments of a few 
tons of trial rock. 

This latter deposit, an impregnated zone in the basal conglo- 
merate of the carboniferous, is about 10 feet thick and occurs 
about 15 feet beneath the top of the stratum. The enriched rock 
continues for an undetermined distance to the west, but on passing 
eastward the bed seems to become barren ; this, too, within a few 
hundred feet. 

The matrix of the impregnated zone is essentially quartz sand* 
a few pebbles being distributed through it in small assemblages 
here and there. As in other instances, the lower half of the zone 
is the richer, carrying at the old quarry breast about 7 per cent, 
of bitumen. The bitumen continually seeps both from the face ofi 
the small openings and from 'the out-crop, forming small pools a 
few inches across at the base of the ledge. 

The deposit of the Green River Asphalt Company is in the 
bitumen bearing sandstone overlying the main basal conglo- 
merate, from which it is separated by 20 to 30 feet of yellow and 
gray shale. 

The bed, as exposed at the time of examination, showed a 
thickness uncovered of about 6 feet, all impregnated, but in vary- 
ing degree, the lower 2.y 2 feet of excellent promise. The sample 
taken by Mr. Eldridge within 5 or 6 feet of the outcrop, yet in 
normal looking rock, yielded about 7 per cent, of bitumen. At 
one point the upper portion of the bed, also, showed considerable 
enrichment, indicating that upon passing beneath cover the entire 
6 feet might become available for shipping. The matrix of the 
rock is a clear, sharp, quartz sand. 

The deposits of bituminous sandstone in Logan county lie in 
its northern half, in the Chester division of the lower carbonifer- 
ous. A single quarry, that of the Standard Asphalt Company, has 




i il I *m\ 







\ 


S3 






" 



ASPHALT PAVING PLANT OF THE ASPHALT CONSTRUCTION 
COMPANY, OF NEW YORK. 



12 



'ASPHALTS' 



BITUMINOUS ASPHALT SANDSTONE ROCK. 53 

been opened, about 5 miles northeast of Russellville, in the Big 
Clifty sandstone. There is also a prospect about 2 miles north- 
west of this at the same horizon. Mr. Averitt also reports one or 
two other deposits, unopened, at this horizon, near Homer, still 
farther north. 

The region about Higginsville, Lafayette county, is the only 
portion of Missouri in which bituminous rock has thus far been 
found, with a possible exception near Odessa, 15 miles west, where 
also, evidences are said to exist. The only attempt at development 
has been by the Higginsville Quarry Company, on land near the 
Soldiers' Home, i l / 2 miles northwest of the town, where a pit 20 
feet in diameter has been made for trial purposes. 

California has several deposits of bituminous sandstone and 
of malthas in sand. The City Street Improvement Co. has exten- 
sive quarries near Santa Cruz. The bituminous sandstones which 
constitute the product of these quarries are essentially an aggre- 
gate of minute to medium-sized quarz grains. In addition to 
these, there is a slight admixture of a feldspar like material sug- 
gestive of the derivation of the sediment from the adjacent gran- 
ite area. There is also present at times a slight amount of iron 
and a clayey looking material in fine grains. 

Only the quartz, however, is conspicuous. This is subangular 
to rounded. It is in the interstices of this rock that the bitumen is 
held to an extent of between 14 and 16 per cent, in the average 
specimen. The rock varies somewhat in hardness, but on the 
whole is soft, crumbling under the sun's heat, very tenacious, and 
gummy to the touch. Its color is normally black to brownish- 
black, weathering to a gray on exposure to the atmosphere. As 
to the coarseness of the material constituting the bed, while the 
mass of it is of a medium grain, there are bodies of small extent 
of coarser stuff, imparting a gritty and at times even a fine con- 
glomerate appearance, the pebbles also being of quartz, though 
occasionally one of clay is found. The temperature of the atmos- 
phere, according as it is cold or hot, renders the rock either brittle 
or soft. 

There is but little variation from the above features in the 
quarries that are opened on the main bed at the lower horizon. 
Moreover, the members of this bed themselves varied but little 
from each other. The company has laid several streets with this 
material in Santa Cruz and some in San Francisco. I understand, 



54 ASPHALTS. [chap. viii. 

Jiiowever, that they have lately laid the ordinary street mixtures 
prepared in eastern cities, using the California pure bitumen with 
.sand added. This is from the fact that freight rates are too ex- 
pensive to allow of any distant freightage on the natural material. 
The same trouble exists in the use of the Kentucky bitumin- 
ous limestones and it can only be used to advantage in the neigh- 
borhood of the mines or in places where exceptionally low rates of 
transportation are obtainable. 



Chapter IX. 
MANJAK AND UINTAITE. 

BARBADOS produces a bitumen which is known as manjak, 
the origin of this nomenclature is indeterminable, it is a 
purely local term and may have been given by the negroes or pos- 
sibly have been handed down from the Indians who inhabited the 
island prior to 1605, when the crew of the "Olive Blossom" took 
possession of the Island in the name of "James King of England 
and of this island." 

The geology of the Island does not seem to afford the positive 
source of the bitumen. From one point of view the land rises in 
a succession of limestone and coral terraces which indicate dif- 
ferent periods of upheaval from the sea. From another there is 
nothing to be seen but a mass of abruptly rising rocks. 

The gullies or ravines, the result no doubt of volcanic agency, 
are very numerous radiating from the high semi-circular ridge of 
the Coralline formation in a very regular manner to the west, 
north and south but not to the East, where the coral rocks end 
abruptly. 

The chalky soil of the district called Scotland (from its as- 
sumed resemblance to the scenery of the Highlands )contains "in- 
fusoria" and is altogether different from the deposits of the coral 
anmials which form the superficial area of six-sevenths of the 
island (91,000 acres). Besides the chalk or marl, sandstone is 
found in this dtstrict. 

The Scotland formation also contains a blue clay sometimes 
interstratified with the sandstone. It is in this section of the 
Island that the bitumen was found and to Mr. Walter Merivale, 
C. E., must be given the credit of exploiting the sources and de- 
veloping the industry of mining the product. 

In a paper read before the Federated Institution of Mining 
Engineers, Mr. Merivale stated that having found the manjak in 
pockets apparently in no great number and of no great size, he 
considered that it suggested the fact that the mineral found in the 



56 ASPHALTS. [chap. IX. 

pockets must have broken off a main body and later having found 
a vien where the ground was not disturbed by slips, his conclusion 
was that there is beneath the island an enormous reservoir of 
liquid bitumen which is still trying to force its way to the surface. 

In the Conset district, there is a hill, or rather a piece of the 
vliff, about 300 feet long, on the coast, called Burnt Hill, which is 
described by Messrs. Jukes-Browne and Harrison, in their pam- 
phlet on the geology of Barbados, as being impregnated with bitu- 
men. Impregnated it certainly has been, but the impregnation 
took place very many feet below the level it at present occupies, 
and before it was thrust up through the calcareous sandstones and 
marls. These still stand on either side of it in alternate strata, 
from 3 to 12 inches thick, exposed on the face of the cliff, and 
rapidly and more rapidly inclined upwards as they near the in- 
truded mass of shale. The shale, moreover, shows no stratifica- 
tion, but is simply a huge mass. Mr. Merivale sunk shafts on both 
sides of it and found it below the marl. This shale or bituminous 
clay, has the following analysis : 

Moisture 7.52 

Ash 76.19 

Carbon 14.32 

Hydrogen (not included in moisture) 1.05 

Oxygen, etc 0.92 

As the shaft increased in depth thin veins of hard manjak were 
found, and others of liquid manjak, and of semi-liquid manjak. In 
the Conset district, the coral capping has been removed, and the 
manjok exposed in more than one spot. 

When met with, some way below the surface, the blue clay is 
soft and treacherous, the fissues, which divide it up into a million 
blocks, contain bitumen or water, and the blocks slide from their 
places as soon as the miner's pick removes the supporting rock or 
manjak from before them. Higher up, the blue clay seems to be 
almost a different formation, and is as hard as rock, not unlike 
chalk, and crossed and recrossed by thin streaks of manjak and 
of gypsum. 

Large quantities of iron pyrites are also found here and there 
in it, in nodules and in very thin veins. 

The manjak veins are thrust up through all the formations 
except the coral, which probably indicates that the intrusion oc- 



en ^ 

O* O 

sl 2 




•ASPHALTS' 



MANJAK AND UINTAITE. 57 

curred before the coral was formed, or it may mean that it occurred 
after it was formed, but was unable to get through it. In the 
latter case, however, the ends of the veins would be flattened out 
against the bottom of the coral, instead of ending in thin streaks 
in the softer lower formation. 

The rain having washed away this lower formation after the 
removal of the coral cap, the thin outcrop is exposed, and at times 
a stream cutting its way down a hillside, carves out a piece of the 
vein that crosses its path, leaving exposed a section of the vein on 
each side of the gully ; or the waves eat away the cliffs, and exhibit 
the cross section of a vein running out to sea. 

It was upon one of these stream exposed veins that Mr. Meri- 
vale began work a few years ago, and it is from this vein or pocket, 
as the geologists are understood still to call it, that he has ex- 
tracted a large tonnage. 

The following are analyses of Merivale manjak and of Trini- 
dad glance-pitch : 

Trinidad 
Merivale Glance- 
manjak. pitch. 

Specific gravity * 1.123 i-*39 

Melting point 420 F. 360 F. 

Matter soluble in carbon bisulphide 97% 88% 

Ash 2.32 7.44 

Ash, color Reddish. Grayish. 

Loss on heating 2.61 9.4* 

Iodine absorption 42.2% 42.0% 

Organic dust 0.69 4.56 

♦Per cent, after heating to 500° F. for two hours. 

Others have followed Mr. Merivale's example and have mined 
the manjak which is in good demand for insulating material, var- 
nishes, waterproof, etc., and it has to a great extent, superseded 
for use in high class varnishes Egyptian and Cyrian asphalts, which 
it closely resembles in composition and appearance. This asphalt 
has not had the advantage of the extensive advertising given to 
other bitumens and the writer does not call to mind the exhibit of 
this mineral at any of the great expositions. 

Possibly the advantages of this method of bringing products 



58 ASPHALTS. [chap. ix. 

before the public is not as popular as hitherto, for it was noticeable 
that at the Pan-American Exposition only one exhibit, that of the 
Barber Asphalt Co., was on view, while at the Chicago "World's 
Fair" a great number of companies were represented. 

Uintaite (gilsonite )is a similar material to the Barbados man- 
jak; it is found in the vicinity of the boundary line (between Col- 
orado and Utah). Professor Eldridge has described it as a black, 
tarry-looking substance of most brilliant luster, normally of ab- 
solutely homogeneous texture, and exceedingly brittle. Its frac- 
ture is coarsely conchoidal. In mining, it gives off a fine chocolate 
brown dust, most penetrating to skin and lungs. Sufficiently near 
the outcrop of the vein to be influenced by atmospheric agencies, 
it loses its brilliant luster for a dead black surface, but a fresh 
fracture, no matter in how small a particle, shows its brilliancy 
still present, indicating a change to an inconsiderable depth only. 

Under atmospheric influences, also, uintaite shows a fine col- 
umnar structure at right angles to the walls of the vein and to a 
distance of about 6 inches from them. This structure has been 
recognized by Wurtz, Lesley and others in grahamite, and by Les- 
ley is called "Pencillate." In addition to the columnar, there may 
be developed a cuboidal structure, in some instances by a further 
transverse separation of the pencillate rays in others independent 
of these. In the upper 10 or 15 feet of a vein the latter structure 
not infrequently prevails through a large proportion of the uin- 
taite, shading laterally into the two pencillate zones at the sides. 
It would seem quite probable that this structure, pencillate and 
cuboidal, is inherent in the material having originated perhaps im- 
mediately after its injection into the fissure from cooling or from 
pressure. 

The walls of the uintaite veins are usually impregnated with 
the mineral to depths of from 6 inches to 2 feet, though the shales, 
on account of their close texture, do not permit this to such a de- 
gree as the sandstones. The line between the impregnated and 
non-impregnated portions of the wall rock is usually somewhat in- 
definite, but instances are not wanting of the sharpest demaraca- 
iton. 

The region in which the unitate (gilsonite) veins are found 
extends between the parallels of 39 degrees 30 minutes and 40 de- 
grees and 30 minutes, and the meridians of 109 degrees and no de- 
grees 10 minutes, or from a point 4 or 5 miles within the Colorado 



MANJAK AND UINTAITE. 59 

line, westward for 60 miles into Utah. Larger veins are somewhat 
scattered, one lying about 3^ miles due east of Fort Duquesne, a 
second in the region of Upper Evacuation Creek, and the two or 
three others of chief importance in the vicinity of White River and 
the Colorado Utah line. Besides these, there is a 14-inch vein near 
the western edge of the area in the vicinity of the fortith parallel ; 
another of equal size about 6 miles southeast of the junction of the 
Green and White rivers ; a third in a gulch 4 or 5 miles northwest 
of Ouray Agency, west of the Duyuesne River, and a number from 
one-sixteenth of an inch to 1 foot in thickness in an area about 10 
miles wide, extending from Willow Creek eastward for 25 miles 
along both sides of the Green and White rivers. 



Chapter X. 
LATE EUROPEAN WORK. 

WHILE preparing this matter the author made a trip to Eu- 
rope and took the opportunity to study there the develop- 
ments in the asphalt industry. He visited Mr. W. H. Delano in 
Paris, whom he found busy in the preparation for putting up works 
on the Mahmoudieh Canal in Alexandria, Egypt, where his com- 
pany have a considerable amount of work to do in compressed 
asphalt. 

A model of bituminous concrete fortification attracted the 
writter's attention and he was informed that a casement 12 meters 
by 6 metres by 4^ metres had been constructed of the same ma- 
terial for the French arm officials in 1886 at the Bourges Camp 
(Department Cher), at which bombshells charged with melinite had 
been fired and that the construction stood the test for fifteen min- 
utes, while one of the same built of hydraulic cement concrete was 
shattered at the first discharge. 

In London the writer met Mr. H. D. Blake, director and gen- 
eral manager of the Limmer Asphalt Paving Company. He stated 
that Limmer mastic and asphalt and Montrotier Seyssel mastic as- 
phalt are mineral rock asphalts prepared only by the company. 
The ungritted mastic asphalt is composed of not less than 15 per 
cent, of bitumen and 85 per cent, of fine rock asphalt powder. The 
gritted mastic asphalt is composed of 15 to 18 per cent, of bitumen 
and from 82 to 85 per cent, of fine rock asphalt powder, with an 
addition of from 10 to 20 per cent, of fine specially prepared grit, 
according to requirements. 

The various purposes to which this company's mastic asphalt 
may be put are almost innumerable, and to merely mention a 
few, Mr. Blake states that these mastic asphalts are being very 
largely adopted by architects, and engineers for roofs, floors, 
bridges, barracks, fortifications, powder magazines, quays, 
wharves, barns, footways, pavements, graneries, drill-grounds, 
breweries, stables, coach-houses, courtyards, railway platforms, 
warehouses, basement floors, covering of railway and other arches, 




TRIMBLE PLACE, NEW YORK, N. Y. 

Paved with Xeuchatel Rock Asphalt Paves, finished with Non- 
Slippery Wearing Surface, cast iron gutter and wheel plates. 



14 



"ASPHALTS' 



LATE EUROPEAN WORK. 6l 

damp course to horizontal walls, vertical work to face of walls, 
swimming baths, skating rinks, tennis courts, lining reservoirs, 
slaughter houses, market places, piggeries, dog kennels, garden 
paths, and playgrounds to public schools of the Metropolis and 
leading provincial towns in the United Kingdom of Great Britain. 

Mineral rock mastic asphalt does not absorb impurities and 
can easily be cleansed, and its introduction into Indian and other 
eastern cities would do much to facilitate the work of sanitation 
now so much needed in the East, especially for the lining of the 
usual open side drains and filth carriers of the bazaars. 

The substitution for the rough and imperfect brick gutters, of 
a smooth jointless surface of mineral rock mastice asphalt would 
prove invaluable, and would do much to remedy their present 
offensiveness and danger. 

Again, mineral rock mastic asphalt used for floors for public 
and private latrines is, for similar reasons, much superior to any 
other kind of flooring, especially on account of its durability, the 
ease and rapidity with which it can be cleaned or repaired, and not 
least, its great sanitary properties, because being jointless no vege- 
table or animal refuse can lodge in crevices and decay. Mineral 
rock mastic asphalt might, with advantage, be introduced into In- 
dian and other eastern hospitals, barracks and public buildings as 
floors, flat roofing with skirting and angle fillets, damp-proof 
courses, vertical work with hot asphalt applied to walls, also for 
damp vertical walls where asphalt mastic plates are fixed and after- 
wards jointed with hot liquid asphalt. 

Thus walls and foundations are made secure against dampness 
of any kind, because after its manipulation the mastic asphalt be- 
comes impervious to air and water, resists fire, does not burn, 
repels vermin, checks vibration and is a non-conductor, and should 
do much to arrest the ravages of rats and white ants and their 
destructive effects of rot in foundations. 

Many other situations in w r hich mineral rock mastic asphalt 
may be advantageously used will readily suggest themselves. It 
may be mentioned, however, that the Limmer Asphalt Paivng 
Co.'s mastic asphalts have been laid in India, Ceylon, China, South 
Africa, etc., establishing the fact that mineral rock aspahlt is, in the 
end, a real economy, and when properly laid withstands the ex- 
tremes of heat, cold and damp, successfully. 

Mr. Blake considers that all horizontal foundation walls to 



62 ASPHALTS. [chap. x. 

buildings should be covered with a thickness of y 2 inch of mastic 
asphalt below the ground level to prevent dampness from arising. 
Vertical walls below ground level should be covered externally by 
applying a thickness of ^ inch vertically, viz., by pointing the 
joints of brickwork with hot mastic asphalt, then applying two 
separate coats against the wall, making in all an average of % inch 
in thickness. Particular care should be taken to connect this 
vertical asphalt with that laid horizontally by adding an angle 
fillet. Amongst many other places that might be named where 
this class of work has recently been most successfully executed, 
are the horizontal and vertical walls of the new Admiralty Build- 
ings, Whitehall. 

Where walls under ground level are of a very damp nature, 
and it is impossible to put up the liquid mastic asphalt in the ordi- 
nary manner, the Limmer Asphalt Paving Company for some 
years past have introduced their special system of mastic asphalt 
plates which can be easily, economically, and successfully used, 
viz., after the mastic asphalt plates are made to the proper size, and 
the backs of which are specially roughed to form a key, the joints 
of the wall are raked out and a thin bed of cement mortar laid on 
the back or rough part of the plate and pressed against the wall, 
fixed in courses with broken joints. When the cement has set, 
make good the joints with hot mastic asphalt; the whole then be- 
comes one solid sheet and is not only damp proof but adds con- 
siderable strength to the walls. 

The same care must be taken in making good the connection 
of the vertical plate work with the horizontal damp course by add- 
ing an angle fillet. These plates are recommended for all walls, 
either internal or external, but in all new buildings it is a great 
advantage to execute the work externally. 

This method is particularly suitable for lining internal and ex- 
ternal damp walls, reservoirs, sewage tanks, strong rooms, etc. 
In the year 1890 this company supplied asphalt for lining the Mala- 
bar Hill Reservoir, Bombay, and sent out a foreman to superintend 
the work, which was carried out to the complete satisfaction of the 
authorities. 

It has always been a difficult matter to lay with any success 
asphalt over suspension bridges, especially on account of the ex- 
cessive vibration. This company, however, recently covered with 
their mastic asphalt the carriageway of the well known Clifton 



LATE EUROPEAN WORK. 63 

Suspension Bridge, near Bristol, England, and successfully got 
over the difficulty by covering the wood flooring with canvas, well 
nailed down, so as to form a surface to receive the mastic asphalt, 
then laid }4 inch of rich bituminous mastic as an elastic bottom 
coat, following with a second layer of less bituminous mastic 1 inch 
thick, making in all i l / 2 inches in thcikness. At special intervals, 
an elastic bituminous joint was specially inserted 1 inch in depth, 
made transversely to prevent the mastic asphalt from cracking. 
This new departure has proved exceedingly satisfactory, the car- 
riageway not suffering at all during the severe and violent gales 
of wind to which this bridge has since been exposed. 

In covering a suspension bridge with a steel bent plating bot- 
tom as a foundation, it has been proved that by filling in the hol- 
lows with Portland Cement Concrete, so as to form the camber to 
receive the mastic asphalt, the cement concrete does not withstand 
the vibration and eventually cracks and crumbles into dust. 

This company recently covered the carriageway and footways 
of the Menai Suspension Bridge over the Menai Straits, North 
Wales, and instead of cement concrete, laid down their bituminous 
rock mastic asphalt concrete, by filling in the hollows of the plat- 
ing to the proper formation of the carriageway, and laid the mastic 
asphalt in two coats in the usual manner with great success. 

In Hamburg the writer met, at the office of Messrs. Prins & 
Sturken, agents of the "Industrie-Gesselschaft fur Steine und Er- 
edn" of Madgeburg, the then managing director of that company, 
Mr. Bruchmann, who informed him that his company was a new 
addition to asphalt producers and that it possesses collective min- 
ing prerogatives over 420 acres, in Madgeburg, and works the 
crude asphaltum beds there on mining principles. 

Magdeburg Asphalt is the name under which the Asphalt 
Products of the Industrial Society for Stone and Earth is known 
in America. The first importation of their mastic was made by the 
Boorman Anderson Asphalt Co. in 1904, and from 1905 to 1908 a 
large quantity has been shipped from Hamburg and Bremen to. 
New York and Philadelphia, and it has been used extensively in 
Western Packing Houses and in such work as the Hall of Chem- 
istry of Syracuse University and on the esplanade of the famous 
Stadium of that institution. 

So far as the Asphalt Industry, in covering its necessities for 
Mastic, Stamping Asphalt, Asphalt Slabs and Goudrons will de- 



64 



ASPHALTS. 



[chap. x. 



pend on German sources, it can only do so by the occurrence of 
the above minerals near Lobsann (in North Alsatia, District of 
Weissenburg and about i^ hours distant from Worth), or through 
the well-known works at Vorwohle (in the Duchy of Brunswick, 
District Holzminden), or those of Limmer (near Hanover). 

Prof. E. Dietrich, of the Royal Technical High School in Ber- 
lin, has therefore in his work on "The Asphalt Streets," in 1882, 
rightly anticipated "that the Vorwohle Rock Asphalt in respect to 
its employment as a material for making streets is possibly des- 
tined to play a part." 

The chemical analyses of the European Crude Asphalt Rock 
gave the following comparative results. (See Table V.) 



Table V. 

ANALYSES OF CRUDE ROCK 

Pure 

Bitumen 

per cent. 

12.32 

14.30 

10.62 

2.40 

5.80 

2.90 

1.40 

0.90 

Industrial Society for Stone and Earth, 
hausen (Krs. Holzminden). 



Rock Asphalt from 
German Materials: 

Lobsan 

Limmer 

Industrie Ges 

Deutsche Asph. Ges 

Hannov. Bau Ges . . 

Haarmann & Co . . . 

Rehder & Co 

Thomae 



< 
o 

O 



Rock Asphalt from 

Foreign Materials : 

Val de Travers 

San Valentino 

Ragusa 

Mons 

Pont du Chateau 



Pure 

Bitumen 

per cent. 

10.15 

8.83 

8.92 

10.20 

11.40 



ASPHALT 

Carbonate 

of lime 

per cent. 

71.43 
67.00 

87.14 
91.85 
89.87 
90.64 
9I-52 
93-75 
Limited, in 

Carbonate 
of lime 
per cent. 
88.40 
80.00 
88.21 
84.63 
77.52 



* 
** 

t 
t, 
f 

f 
t 
Eschers- 



N. B.— Analysis results: 

* according to Dietrich. 
** according to Dr. Fritsch & Venator. 

t according to our own factory laboratory. 

t according to Experimental Station in Forli. 




SIDEWALK CORNER OF SMITHFIE'LD STREET AND 5TH AVENUE, PITTSBURG. 

Laid with Kentucky Rock Asphalt Mastic by The Wadsworth Stone 
& Paving Company. 



15 



'ASPHALTS' 



LATE EUROPEAN WORK. 65 

The Vorwohle and Limmer works have united and formed a 
syndicate in the Vorwohle Asphalt Verkaufs Verein (Society for 
the sale of Vorwohle Asphalt) to which at present belong the mines 
and factories of R. Thomae, Render & Co. (Vorwohle Asphalt 
Co.), L. Haarmann & Co., the Deutsche Asphalt Actien Gessll- 
schaft, the United Limmer and Vorwohle Rock Asphalt Company 
and the Hannoversche Bau Gesellschaft. 

The Asphalt mining district belonging to the Industrial Com- 
pany comprise about 420 Brunswick Morgen of 2,500 square me- 
ters = 105 hectares, that is, they alone possess more Asphalt land 
than all the other Vorwohler Asphalt works taken together. The 
borings carried out up to the present, and other mining operations, 
have proved that their Rock Asphalt exists in a thickness of eleven 
metres, of which only about four metres square are worked first of 
all, in the first level by means of galleries and drifts as well as 
transverse headings. According to the report of Dr. F. Rinne, 
Professor of Geology, and Mr. Hoyer, Mining Engineer, both of 
the Royal Technical High School in Hanover, the rock which 
has been already reached suffices for at least 40 years in its 
whole extent, supposing the output to be daily 10 double 
loads. 

Their Asphalt Rock and crude powder are especially adapted 
for mixing with the fatter foreign Asphalt material from San Val- 
entino, Mons, etc., on account of their considerable yield of bitu- 
men and high percentage of lime, as well as the perfect freedom 
from deleterious secondary substances. 

For their Asphalt Mastic they guarantee at least 14 per cent, 
bitumen, which, according to experience, means a considerable 
saving in Goudron when renewed preparation for laying streets 
is in question. All authorities agree in the opinion, that the single 
particles in the asphalt limestone, as well as in its later products, 
viz. : Mastic, Stamp asphalt, etc., are no longer held together by 
molecular cohesion, or by a stony cement but only by the asphalt 
as a bituminous cement. Thus this bitumen guarantee is of the 
highest importance for every one using Asphalt, on account of the 
resistance, elasticity and durableness of the Asphalt materials em- 
ployed in street laying and for other purposes. 

Brunswick Asphalt Mastic. — This material has been imported 
for the last thirty years by Gabriel & Schall, of New York. It has 
been laid in many public and private structures throughout the 



66 ASPHALTS. [chap. x. 

United States, and has proved eminently satisfactory to the owner, 
architect and contractor. 

To insure the protection of the trade, the genuine material is 
put up in cakes cylindrical in shape, weighing from 54-55 lbs. each, 
and branded under the registered trade mark (G & S). 

By permission of the importers we present the analyses 
shown in Table VI. on this and following page : 

Table VI. 

ANALYSES OF BRUNSWICK ASPHALT ROCK, ASPHALT 
MASTIC AND ASPHALT PAVEMENT. 

Brunswick Asphalt Rock. 

Asphaltic bitumen, per cent 9.70 

Carbonate of lime, per cent 90.30 

100.00 
Brunswick Asphalt Mastic. 

Asphaltic bitumen, per cent 15.42 

Carbonate of lime, per cent 84.58 

100.00 
Brunswick Apshalt Pavement. 
As laid in basement of 276 Canal Street, New York City: 

Asphaltic bitumen, per cent 13-44 

Grit, per cent 35-00 

Carbonate of lime, per cent 51.56 



100.00 
COMPARATIVE ANALYSES. 

Neufchatel Rock, asphaltic bitumen from 12 to 13 per cent. 
Seyssel Rock, asphaltic bitumen from 8 to 9 per cent. 
Brunswick Rock, asphaltic bitumen 9.70 per cent. 

COMPARATIVE TESTS OF THE ASPHALT ROCK SUB- 
MITTED TO HEAT. 

Seyssel Rock disintegrates at 250 degrees Fahr. 
Brunswick Rock disintegrates at 250 degrees Fahr. 
Neufchatel Rock disintegrates at 200 degrees Fahr. 



LATE EUROPEAN WORK. 67 

Table VI. — Continued. 

COMPARATIVE TESTS OF THE THREE ASPHALT MAS- 
TICS SUBMITTED TO HEAT. 

The results are identical for all three. 
Malleable at 90 degrees Fahr. 
Soft at 100 degrees Fahr. 
Plastic at 250 degrees Fahr. 

The fire tests were also applied to the different Mastics with 
equally good results. 

Fire tests, Neufchatel Mastics, 315 degrees Fahr. 
Fire tests, Seyssel Mastic, 330 degrees Fahr. 
Fire tests, Brunswick Mastic, 320 degrees Fahr. 

CONCLUSION. 

The above results are evidences of the similarity of the three 
named Asphalt Mastics, and the Brunswick Asphaltic Rock is 
almost identical with the Seyssel Asphaltic Rock. 

(Signed) E. J. De SMEDT, Chemist. 

In regard to this class of Mastic, so many inquiries have been 
made into the Modus Operandi that the following practical in- 
structions, prepared by David E. Sayre, when Superintendent of 
the New York Mastic Works, are appended : 

Kettle will lay about 100 to 105 feet i-inch work. Dimen- 
sions : Drum, 3 feet 6 inches high; kettle, 1 foot 7 inches deep 
and 3 feet 4 inches wide. Use about 14 blocks Mastic and about 
50 pounds Bitumen, with about 600 pounds Grit for ordinary out- 
door walks. For indoor work about 13 blocks Mastic, 80 pounds 
Trinidad and 600 pounds Grit for floors that will be used severely 
by setting chairs, etc., on them. This would not do for a cold 
cellar. For this use the same combination as for outdoor work, 
or you are liable to have a crack in the asphalt. For this indoor 
work you should see that the kettles are thoroughly and almost 
continually stirred, and particularly from the outside of the bot- 
tom of the kettle. The stirrers should be driven down, scraping 
the side and bottom of the kettle. You should have also a scraper 
with handle about 54 inches long, scraper about 3 inches wide, 
scraper made from best steel, and kept sharp, with which to 



68 ASPHALTS. [chap. x. 

scrape the sides and particularly the bottoms of your kettles each 
evening until the iron shows plainly. When the kettles are warm 
have a board laid across the top of kettle, the bottom chopped 
and scraped clean with the long-handled scraper. We would sug- 
gest for quadrille work to have four additional squares added to 
your stamp, start your line and set stamp first time straight, then 
each additional time set two blocks over the last figure made in 
the work. This., with a little care, will keep your lines straight with- 
out using the line more than once. We think you will find kettles 
made in one piece preferable to those with loose bottoms; also 
have a heavy angle iron around the top and bottom of the drum, 
projecting inside. This supports the kettle on the top and 
strengthens it on the bottom, also leaving a smooth surface so 
the drums will roll easily. Have your kettle fit in drum neatly, 
but not too tight, so they will not spill out in rolling and yet can 
be taken out and put in without too much trouble. The stirrers 
should have a face about 7 inches wide and scraping edge about 
2. to 2)2 inches and kept fairly sharp. 

In laying asphalt always be sure that the concrete is fully up 
to grade line and a level, even surface, as cement and sand are 
much cheaper than asphalt, besides a spreader cannot do first- 
class work when attempting to spread uneven thicknesses of as- 
phalt. You do not need an absolutely smooth surface, but an 
even one without depressions or bumps in it, and not too dry. 
Try and lay the asphalt before the concrete turns white, and just 
after it has set firmly, as it will blister from the concrete being 
either too wet or too dry. You will find the above proportions 
for indoor work will cause complaints from your labor, as it will 
be very stiff and will require extra hard work to either stir or 
spread, and will require good strong men, and should be well 
rubbed with sand. The men may kick, but your work will be sat- 
isfactory to the party having you do the work and a source of 
satisfaction to you as well. 

Be careful that the asphalt does not get burned in the bottom 
of the kettle. It is a good idea to have the last few shovels of ma- 
terial emptied into another kettle, and well stirred into it. We 
find one never gets the kettles stirred too much after the grit is 
put in before that it is not so necessary. In laying good stiff work 
use 3^-inch iron guide bars, and you will get your full inch, and 
on down for thinner layers ; only you will find your material will 



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16 



'ASPHALTS' 



LATE EUROPEAN WORK. 69 

have to be softer as it is laid thinner, and to make it so requires 
more Mastic and Bitumen or Trinidad. Always see that the joints 
are well heated before final sprading, keeping some hot stuff 
ahead of the work on the asphalt the spreader is joining; rub 
joints extra well. 



Chapter XL 
TURKISH AND OTHER BITUMENS. 

WHEN in London I found that a Trukish bitumen was being 
used for fluxing purposes and since had the pleasure of 
meeting Professor J. Edward Spurr, of the U. S. Geological Sur- 
vey, who had just returned from Constantinople. He furnished 
me with the following interesting information : 

On the southwestern coast of Asia Minor, north of Cape 
Chelidonia, is the famous ancient Chimaera of the Greek stories. 
Here gases are continually disengaged from fissures and are 
known to have been burning for 2,800 years atleast, for the phe- 
nomenon was described by Hesiod before the time of Homer. 
Tchiatchefr", the Russian geologist, states that the gas is emitted 
from fissures in serpentine (altered igneous rock) intrusive into 
limestone. 

It is interesting to note in this connection that burning foun- 
tains of gas were long known in the Baku oil fields, beforethe dis- 
covery of oil there. There is also on the coast of Albania (east 
shore of the Adriatic) the locality Polina, near Durezzo, where 
gas emanates from the summit of a hill and often accidentally 
takes fire. The hill is said to be igneous, but the existence at the 
foot of it of an asphalt spring suggests an organic rather than a 
volcanic origin for the gas. Petroleum also has been reported 
from here and seems to have been exported on a small scale. This 
hill was the ancient Apollinia, and here the priestess of the famed 
Delphic oracle sat and inhaled the fumes of gas, till dazed, when 
her words were regarded as inspired. 

It is, therefore, an open question as to whether the escaping 
gas of the Chimaera (the modern Turkish name is Yanartash 
"stone that burns" is of organic origin, and indicates oil below, 
or is volcanic ; but the chances are perhaps in favor of the former 
alternative, especially as the igneous rock? of the locality (altered 
peridotite) is not one that indicates recent volcanic activitv. 



TURKISH AND OTHER BITUMENS. 71 

As is perhaps most often the case, there seems to be a general 
connection between petroleum and natural asphalt in the Turkish 
Empire. Asphalt deposits are known in a number of lacalities, 
of which the best known are in Albania, near the Adriatic and in 
Palestine. 

In Albania asphalt occurs at the foot of the hill of the Delphic 
oracle, as mentioned above, also in a large bed near Avlona and 
other places. This asphalt was mined by the anceints and is men- 
tioned by Posidonius. The chief producing locality is now Selin- 
itza, which is worked by the Imperial Ottoman Bank. The as- 
phalt is not of the highest quality, bringing about $13 a ton in 
Trieste. Asphalt is reported from the Province of Monastir in 
European Turkey. 

The asphalt in the region of the Dead Sea (Lake Asphaltites) 
has long been noted. There are bituminous springs at Nebi Musa 
which contain 30 to 40 per cent, asphalt. 

What is commercially known as the Syrian asphalt is ex- 
ploited near Hasbaya, in the Province of Damas, by the Civil List 
of the Sultan. The mineral is hard and of a brilliant lustre, with a 
marked odor. It is of great purity, and is, therefore, used entirely 
in the manufacture of varnishes and aniline dyes. It has been 
chiefly marketed at Trieste, where it is quoted at $84.00 per ton, 
boxed and delivered. The demand is, however, limited, so that the 
yearly output is only a few hundred tons. 

An Anglo-German company with headquarters in Constanti- 
nople, has been formed to work other deposits in Palestine, but 
so far they have not obtained the concession. 

Bituminous schists are found near Beyrout. Some movement 
has been made towards working them and a large trial lot has 
been sent to England, but so far there has been no real activity. 

Dr. Edgar James Banks, formerly American Consul at Bag- 
dad, and now director of the Urarchaeological Exploring Expedi- 
tion, states that there are springs of bitumen opposite the town of 
Nasarieh, Province of Busreh, about 100 miles trom the site of 
Babylon. The deposits are near a navigable river, but are not 
exploited, save that the material is to a certain extent used by 
the natives as a cement in building, and as a substitute for sealing 
wax. 

In Amsterdam, the writer went over the works of the Neu- 
chatel Asphalt Co. with the resident manager, Mr. J. Patten 



72 ASPHALTS. [chap. XI. 

Walsh, who pointed out one of the recent improvements in the 
laying of compressed asphalt streets through the use of mastic 
adjoining tramway rails and where the asphalt pavement came in 
conjunction with pavements of other material. Repairs to the 
asphalt streets necessitated by gas leakage attracted attention as 
in streets laid ten years there were no other defects. 

A report on this subject by Dr. James C. Bayles, M. E., at 
a Convention of the League of American Municipalities is in- 
teresting in this connection. Dr. Bayles says that in case of 
asphalt, the destruction due to gas leakage is rapid and complete. 
The first surface indication is a depression marked with parallel 
striations in the direction of the movement of traffic. This indi- 
cates that the binder has been decomposed, allowing the super- 
ficial layer to yield under the wheels of vehicles. A bar hole put 
down through such a spot will always find a gas leak. Gas may 
also be found in large quantities under sound asphalt — a phenom- 
enon which has given rise to some confusion. 

The explanation is really very simple. What rots the binder 
of the asphalt pavement is neither the hydrogen nor the carbon 
monoxide. In fact, uncarburetted water gas would not touch it. 
The mischief is done by the naphtha enrichments composing the 
olefiant series. These are high solvents of everything bituminous. 
Gas which leaks from a buried pipe works its way upward until it 
strikes the binder of the asphalt. This is attacked by the olefiants, 
and decomposed. The gas, returned to the composition of uncar- 
buretted water gas and inert, so far as asphalt is concerned, works 
its way in all directions until it finds some avenue of escape. 

One of the largest industries in connection with bitumen is 
the manufacture and application of bitumen damp course and 
sheeting and the laying of conduits with bitumen. The writer 
met Mr. Thomas Callender, Chairman of the Board of Directors 
of Callender's Cable and Construction Co., in London, and was 
surprised to hear that the company had at that time seven thou- 
sand men at work in their large factory at Belvedere and on the 
work they were constructing. 

Mr. George M. Callender called attention to an opinion given 
by Mr. Allan Greenwell, A. M., I. C. E., who prefaced his views 
with the statement : " 'The art of directing the great sources of 
power in nature for the use and convenience of man' is the apt 
definition given by the late Thomas Telford of that species of 



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'ASPHALTS' 



TURKISH AND OTHER BITUMENS. 73 

knowledge which constitutes the profession of a civil engineer, and 
is perpetuated in the Charter of the Institution of Civil Engineers. 
In the acquisition of this knowledge the civil engineer has to make 
himself acquainted with the various physical properties possessed 
in varying degrees by the different forms of matter.'" 

Mr. Greenwell further states that asphaltic materials are now 
being largely used in order to render works impervious to water. 
They possess the advantage of small relative bulk, ease and 
rapidity in laying, and claim to possess sufficient elasticity in 
order to accommodate themselves to slight alterations in the 
shape or condition of structures due to the subsidence, expansion 
or contraction or other causes. 

In considering these materials a distinction must be drawn be- 
tween : 

(a) Pure asphalt or bitumen. 

(b) Rock asphalt or bitumen and calcareous rock. 

(c) Artificial asphalt, manufactured with coal products. 

Artificial asphalt has been introduced to the engineering pro- 
fession under many forms, but each form in turn has proved to be 
unreliable, absence of elasticity resulting in fracture and Assuring, 
being its constant defect. The unfortunate popular lack of knowl- 
edge as to the real nature of bitumen, and its essential difference 
from artificial or so-called tar asphalt has, however frequently per- 
mitted the substitution of the latter for the former causing incal- 
culable detriment to the proper appreciation of the pure substance. 

Rock asphalt although a natural substance containing pure 
bitumen, is also wanting in elasticity, and is therefore not adapted 
for works where imperviousness to water under all circumstances 
is a sine qua non. 

Pure bitumen appears to possess those qualities, including 
elasticity, which are requisite in a perfect waterproofing material 
for use in engineering works, and experience of its use under most 
trying circumstances leads to the conclusion that it may be classed 
as an absolutely reliable material, for which a great future may be 
safely predicted. 

In Mexico there are nummerous deposits of asphalt princi- 
pally of the maltha or liquid grade ; it has been found in numerous 
deposits from the Panuco River to the Isthmus of Tehuantepec. 
While a few hundred tons of this material have been shipped to 
the United States, the expense of getting it here has been so great 



74 ASPHALTS. [chap. XI. 

that its use has been abandoned. From this country, also, comes 
the Chapopota asphalt used for varnishes but generally superseded 
in use by less expensive asphalts of a similar nature. 

In the last report of the U. S. Geological Survey an occur- 
rence of bitumen was reported in Oklahoma about 3 miles south- 
east of Fort Sill. From recent information received from Captain 
Farrand Sayre, U. S. Cavalry, then stationed there, the deposit 
is known as "Tar Spring," a black substance oozes out from the 
ground which is now believed to be petroleum. A well has been 
bored near it in the hope of finding mineral oil, and natural gas 
has geen found. No bituminous limestones or sandstones are 
known to be in the region. 

The latest commercial development of asphalt is the refinery 
of the United States and Venezuela Co. erected near Maracaibo, 
where is refined the product of an asphalt lake containing 97 acres 
area of solid bitumen. This refinery with other improvements cost 
about $500,000, and large quantities of the refined material have 
already been brought to this market. Professor Stillman, of the 
Stevens Institute of Technology gives the analysis of the asphalt 
as follows : 

Crude. Refined. 

Bitumen 94-13 99-07 

Woody fibre, etc 4.85 0.25 

Ash 1.02 0.68 



100.00 100.00 

and adds 'The Refined Asphalt is of very superior quality." Ralph 
T. Rokeby, the President of the company, evolved the idea of fill- 
ing the refined asphalt into bags which has proved a wise innova- 
tion, as the saving in cost of the weight of these packages as 
against the heavy wooden barrels generally used is a great benefit 
to the purchasers.* 



* Author's Note: Owing to troubles with the Venezuelan Government it has 
been impossible for the last three years to import this material from Maracaibo. 



Chapter XII. 

DEVELOPMENTS OF THE ASPHALT INDUSTRY UP TO 

1903. 

DEVELOPMENTS of the Asphalt Industry up to 1903 were 
so ably treated on before the Institution of Civil Engineers 
in London, by his long tiem friend and coadjutor, William Henry 
Delano, of the Val de Travers Asphalte Paving Co., that the 
author has given his paper, "Recent Developments of the Asphalt 
Industry," verbatim. 

"Since 1880, when a paper* by the author on "The Use of 
Asphalt and Mineral Bitumen in Engineering," was read before a 
meeting of the Institution, the employment of the material has so 
largely increased that it may be worth while to take a retrospec- 
tive view, and a glance into the future of this industry, in which 
so much British capital is invested, and the development of which 
gives employment to so many engineers. 

"Asphalt, is a natural product, and consists of limestone im- 
pregnated with pure mineral bitumen. Its ideal composition is 
80 per cent, to 90 per cent, of pure carbonate of lime, and 10 per 
cent, to 20 per cent, of pure mineral bitumen. Bitumen is natural 
mineral pitch, composed of 85 per cent, of carbon, 12 per cent, of 
hydrogen and 3 per cent, of oxygen. It is only found pure in the 
rock which it permeated when in a state of vapor, and under enor- 
mous pressure. The recent eruption of Mount Pelee, in Martin- 
ique, affords evidence of the great heat and pressure caused by the 
combustion of bituminous vapors. Mineral bitumen should not be 
confounded with the residuum of crude petroleum, naphtha, shale, 
or animal fats, nor, above all, with gas-tars : these contani dyes, 
which natural bitumen does not. As asphalt and bitumen are 



♦Read before the Institution of Civil Engineers, London, Eng-. Ses- 
sions 1902-1903. 



y6 ASPHALTS. [chap. XII. 

natural products, they vary in quality and must be taken as Nature 
produces them. Thus the limestone in the Sicilian variety of 
asphalt is of coarse grain; but in Seyssel, Val de Travers and 
Servas asphalts the grain is fine, so that the specific gravity of 
Sicilian asphalt is less than that of the other rocks named. The 
bitumen contained in Seyssel and Sicilian asphalts is solid and 
tough, whereas that contained in Val de Travers asphalt is oily. 

"The author having experienced much trouble due to waves 
and buckling in roadways of Val de Travers asphalt under heavy 
traffic and exposure to hot suns, consulted the later Mr. Schutzen- 
berger, Professor of Chemistry at the College de France, who had 
made a special study of hydro-carbons. This eminent chemist, 
after separating the bitumen from the pulverized rock by dissolv- 
ing it in carbon di-sulphide and filtering the solution, heated the 
bitumen in vacuo without obtaining any appreciable evaporation; 
when the heat was increased the bitumen decomposed. This 
showed that the oil could not be got rid of by heat, and led the 
author to blend Seyssel with Val de Travers, and subsequently with 
Servas rock, with satisfactory results. By blending, asphalt pow- 
der for roadways can be obtained suitable for tropical or temperate 
climates. 

"The molecules of natural asphalt are held together, not by 
cohesion, but by bituminous agglutination. Mr. Leon Malo found 
that the test for asphalt is to heat a small piece on a hot iron 
plate, when it will fall to pieces. To test its compressibility, a small 
hydraulic press with appropriate molds, or a tube with a plug and 
hammer, may be used. Some asphalts, after being subjected to a 
pressure of 6 tons per square inch, will crumble under pressure of 
the fingers. The unimpregnated limestone found in an asphalt 
mine will not crumble on being heated. 

"Asphalt mastic is composed of asphalt powder and refined 
bitumen, mixed mechanically in a boiler under heat. The mixture, 
after being heated to, say, 400 F., is run into molds, the blocks 
weighing about 56 pounds. It should contain about 15 per cent, of 
bitumen, native and added, and will not fall to pieces on being 
heated, as asphalt rock does, nor will it compress. Mr. Malo has 
pointed out that in a layer of compressed asphalt the top of the 
layer is always denser than the bottom, even when the thickness 
has been reduced by wear to ^2 inch. The surface, therefore, 
always rests on a cushion. To make good mastic, care and experi- 



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'ASPHALTS' 



ASPHALT INDUSTRY TO 1003. yy 

ence are required. It must be made of blended rocks, ground very 
fine, mixed with refined bitumen and thoroughly cooked ; it cannot 
be too pure. For footpaths, grit is added to it, say, 33 per cent, 
for temperate, and 50 per cent, for tropical climates. Clay, pyrites 
and vegetable matter are all detrimental, whilst taking up the place 
of good material. The qualities of asphalt, bitumen, and their 
product, mastic, are remarkable, and are daily being more and 
more appreciated in engineering work. 

"Asphalt makes noiseless roadways, is impervious to water, 
and produces no dust or mud; mastic makes footpaths like a car- 
pet, arrests capillarity, is air-, water- and vermin-proof, absorbs 
vibration and is a non-conductor of electricity. By mixing bitu- 
men with pure silex, a mastic can be made which resists acids. 

"The Island of Sicily alone now produces annually 75,000 tons 
of natural asphalt, sufficient to lay 812,000 square yards of com- 
pressed asphalt, 2 inches in thickness; whilst the output of the 
other mines in Europe (Seyssel, Val de Travers, Chieti in the 
Abruzzi, Limmer, Vorwohle, Lobsann, Auvergne and Syzrane in 
Russia) may be estimated at 120,000 tons annually; whereas pre- 
viously to 1870 the Seyssel and Val de Travers mines were the 
only ones of repute, and their combined annual output was about 
50,000 tons. When in the United States some five years ago, the 
author noticed that one American Company, managed by a Col- 
onel of Engineers, had an army of 18,000 men employed daily in 
laying bituminous compounds for roadways in different towns of 
the Union. Often the process followed was to construct the roads 
first, and to build the towns afterwards ; where money was not 
available, payments were effected in bonds on land, or even on 
produce. The author's experience has been acquired chiefly in 
France, where the asphalt industry originated, and where the 
special plant and tools, now used everywhere, were invented and 
elaborated. 

"In 1872 the author was called upon to undertake the man- 
agement of the original Asphalt Company, which had the contract 
for all the compressed asphalt roadways for the town of Paris. 
These roadways were then being laid on hydraulic-lime concrete, 
only 4 inches in thickness — actually the same thickness as for 
footpaths — and of this y 2 inch thickness consisted of a mortar 
floating, spread upon the concrete after it had been laid, which 
crumbled under the blows of the rammers used in ramming the 



7 S ASPHALTS. [chap. xii. 

hot asphalt-powder to make the road. On the author's recom- 
mendation, Portland-cement concrete was laid, at the company's 
expense, in the Rue d'Antin, and this work stands to the present 
day ; the old streets, however, were all laid on lime concrete. Some 
of the engineers of the town of Paris who had the superitnndence 
of the works declined to have Portland-cement concrete at any 
cost, and at the end of five years, when the concrete wore out, the 
company had lost £40,000, owing to the onerous conditions of the 
maintenance contract, by which they were paid 1 franc per square 
metre per annum for all repairs, including the relaying of one- 
tenth of the surface annually and setting the whole in order at 
the end of the contract. When holes in the asphalt had to be 
repaired, the crumbling concrete had to be relaid also, but, owing 
to the exigencies of traffic, it had not sufficient time to set, so that 
work was carried out under grave difficulties ; and in rainy 
weather, in order to get a dry surface for the hot powder, it was 
necessary to use bituminous concrete, or at least a layer of liquid 
asphalt. 

"In general, yielding materials like asphalt require a rigid and 
resisting concrete, and floating is undesirable. Finding how detri- 
mental to the asphalt roads was the greasy mud brought from 
macadam and stonepitching, the author presented the town of 
Paris with one hundred india rubber squeegees, and this led to the 
adoption and manufacture of these tools in France. He also de- 
signed a special form of water cart for cleaning asphalt roadways, 
the sprinkling being effected in front of the horses, sa well as be- 
hind them, the French plan of flushing with a fireman's hose and 
nozzle being impracticable in narrow streets or in windy weather. 
The extreme gradient for an asphalt roadway is 1 in 30, and the 
camber between the outside edge of the gutter and the crown of 
the road should not present gradients of more than 1 in 50. 

"In 1884 the town of Paris made a 10-years' contract with the 
author's company, by which they agreed to pay, for a 2-inch layer 
of compressed asphalt, 14 francs per square metre (9s. 4d. per 
square yard) and for a 6-inch layer of Portland-cement concrete 
Sy 2 francs per square metre (3s. 8d. per square yard), and for 
maintenance 2 francs per square metre (is. 4d. per square yard) 
per annum, with the undertaking that all the streets laid with lime 
concretes should be relaid with Portland-cement concrete, the 
town paying for the repairs on those streets apart, until the sub- 



ASPHALT INDUSTRY TO 1003. 79 

stitution should take place. It was in 1884 that Sicilian asphalt 
was accepted for the first time, the Paris engineers having been 
commissioned to visit and report on every asphalt mine then 
known, and it took the place of St. Jean de Marvejols asphalt, 
being cheaper. A branch of the London Limmer Asphalt Com- 
pany obtained the contract for about one-third of Paris, but after- 
wards passed over their contract to a French company, formed by 
the Neuchatel Company, Limited, which holds the concession for 
the Val de Travers mines, who had not renewed their concession 
to the author's company. It is notable that English capital had 
absorbed the asphalt industry originated in France, and led to its 
development all over the world. 

"The, town of Paris allowed the contractor to grind up the 
pieces of old compressed asphalt from gas trenches and repairs, 
and to convert it into mastic for the liquid gritted asphalt foot- 
paths ; but it would not allow the old gritted mastic from the foot- 
paths to be used again for new works or relayings ; this could only 
be used for small repairs and trenches, and even then only if mixed 
with an equal quantity of new material. The area of the asphalt 
mastic footpaths in Paris is about 6,000,000 square yards ; this 
material provides a surface which is less fatiguing to walk on, and 
much more agreeable to the sensitive human foot, than granite, 
stone, or hard cement. The town paid 35 centimes per square 
metre (2.8d. per square yard) per annum for the maintenance of 
the footpaths, laid 15 millimetres (9/16 inch) in thickness, for all 
repairs arising from wear and tear, including the re-laying of one- 
fifteenth part of the entire surface every year, whether wanted or 
not. The thickness of the layer being 15 millimetres, and the wear 
of the surface of the surface being estimated at 1 millimetre per 
annum, it was supposed that at the end of 15 years the whole sur- 
face would be re-laid. In practice, howeve, it was found that the 
narrow streets in the centre of the town wore out in 5, 6, or 10 
years, owing to the heavy traffic, whereas those in the suburbs 
were as good at the end of 15 years as on the day they were laid. 
Knowing that old mastic, remelted with fresh bitumen (the main 
ingredient of asphalt), is just as good as, if not better than, new 
inastic, owing to the second fusion, the author proposed to lay all 
surfaces 20 millimetres (% inch) thick, instead of 15 millimetres 
(9/i6inch), using a mixture of equal quantities of old and new mas- 
tic, already admitted for repairs and trenches, and to suppress the 



80 ASPHALTS. [chap. xii. 

obligation to re-lay one fifteenth part of the surface annually, only 
re-laying what was necessary, thus saving annoyance to house- 
holders and unnecessary carting, whilst the contractor got rid of 
materials easily that otherwise he had to sell to suburban corpora- 
tions, private undertakings, etc. The proposal was agreed to, and 
this arrangement has been continued ever since, to the general 
advantage of all concerned. The concrete used with compressed 
asphalt prepared in this way is composed of washed flint pebbles, 
river sand, and best Portland cement, gauged 4, 3 and 1. The 
cement, not more than 2 months old, is first turned over dry, then 
mixed wet, being sprinkled just enough to hydrate it. No floating 
is required. A level surface is obtained by using a straight-edge 
and smoothing the mass with a flat rectangular shovel, filling up 
any cavities with a little mortar, composed of 3 of sand and 1 of 
cement, mixed on the spot. By this plan the whole mass sets at 
the same" time, which is absolutely necessary for hot asphalt 
powder, whereas for wood or cold asphalt slabs this is not neces- 
sary. It is well to allow 5 days for setting in summer, or 7 days 
in winter, and the surface must be dry, otherwise the powder, 
heated to 300 F., would convert any moisture into steam, which, 
in passing through the asphalt, would give rise to nodules. For 
liquid-asphalt footpaths, hydraulic-lime concrete may be used, and 
a mortar floating, in order to get a true surface with a straight- 
edge, and to prevent more asphalt being laid than the thickness 
warrants. A ^4-inch layer weighs 80 lbs. to the square yard. 

Perhaps the best method of protecting any work in masonry, 
or iron vaults, roofs, reservoirs, etc., is by means of two layers of 
pure asphalt, 2/5 inch in thickness, superposed, the joints of the 
first layer being covered; a recess can be cut into the masonry and 
the fillet pressed in. Such a layer will weigh about 68 lbs. per 
square yard. A damp-course laid in walls of buildings, at a level 
of about 1 foot above the ground, will stop capillarity and preserve 
the buildings from the action of water and frost. To keep out 
damp is as much a necessity of hygiene as good drainage. The 
Egyptian Sphinx, the Pyramids, and so many tombs and buildings, 
not to mention more recent Roman buildings in Africa, have sur- 
vived mainly because the chief elements of decay, water and frost 
are absent ; if such constructions had been in England, the expan- 
sion caused by frost and the contraction caused by thaw would 
speedily have disintegrated them. In many brick and stone rail- 



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19 



'ASPHALTS' 



ASPHALT INDUSTRY TO 1903. 8l 

way arches in Paris, water drips through the joints after prolonged 
rain. The Pont du Jour, a stone viaduct over the Seine at Auteuil, 
is full of water in rainy weather, and from certain joints water runs 
out as from a spring. Mr. Barabant, the Manager of the Eastern 
Railway of France, who, as Ordinary Engineer, and subsequently 
as Chief Engineer, of the town of Paris, had special opportunities 
of studying asphalt — having had the Municipal Laboratory under 
his charge — has had all the bridges and viaducts on the ordinary 
and strategic lines between Paris and the frontier laid with pure 
asphalt coating, and has had the platforms of the Paris and Nancy 
stations laid in compressed asphalt slabs and powder. The Paris, 
Lyons and Mediterranean, Orleans, Midi, North and West Rail- 
way Companies have largely used Seyssel asphalt for platforms, 
bridges, viaducts, etc. 

"It has been abundantly proved that asphalt mastic is un- 
affected by cold or heat, i. e., expansion and contraction do not 
alter its qualities. The late Captain Coignet had some of the 
Seyssel asphalt coating from the bomb-proof casemates of the 
Donjon of Vincennes taken up, after laying entombed since 1833, 
and found that no change had taken place in the asphalt. A root 
of lucerne, 5 to 6 yards in length, had tried in vain to penetrate 
the layer. Asphalt has the defects of its qualities, for in foggy 
weather the moisture in the atmosphere will condense on the 
asphalted surface of the casemates, and must be swabbed off. This 
is better than letting it soak into an ordinary soil. But, for this 
reason, in asphalted railway stations, flour, cement and lime must 
be kept off the ground by wooden frames. The gradual disinteg- 
ration of walls and floors is sometimes traceable to the ravages 
of rats and mice ; they will nibble through concrete, but they leave 
asphalt alone. Being a non-fermenting and non-decaying mate- 
rial, it affords no home for insects. A floor laid on joists fixed on 
liquid asphalt is safe from vermin, and there need not be any 
appreciable space between the asphalt coating and the upper floor- 
ing. In the case of fire, asphalt keeps out the air, and holds water ; 
when the wood-work below it has been burned away, it will fall 
like a wet blanket on the flames and extinguish them. This qual- 
ity was proved by the experiments made by the Omnibus and 
Cab Companies in Paris, with the result that the floors of gran- 
aries and silos, wash-houses, stables and mangers are now gen- 
erally coated with liquid asphalt. It was found by Messrs. Tourtel 



82 ASPHALTS. [chap. xii. 

Freres, of Tantonville, near Nancy, that whereas gas tar gave a 
disagreeable flavor to malt, natural asphalt was absolutely neutral ; 
this has led to its adoption for flooring in many breweries and 
makings. Slabs of asphalt of various sizes and thicknesses, made 
made in a hydraulic press, are now manufactured largely and sent 
to all parts of the world. They are laid on Portland-cement con- 
crete similarly to asphalt power, but are fixed in a wet layer of 
pure Portland-cement mortar; after being laid, cement grout is 
poured into the scarcely perceptible joints, and swept off with saw- 
dust when dry. These slabs stand well in streets and courtyards 
where there is little traffic, and require no costly plant, as does 
powder; they can be laid on wet concrete, but, as they have at- 
tained their ultimate compression, wear begins at once. 

"A method of laying asphalt powder cold, by mixing it with 
petroleum essence and a solution of india-rubber, which softens the 
bitumen contained in the rock and so facilitates compression, the 
petroleum afterwards evaporating, has been recently employed in 
Marseilles, Antibes, Barcelona, Aix-les-Bains, Toulon, Nice and 
St. Etienne. By this process work can be done in rainy weather. 

"Just as plasterers mix cow-hair with their plaster, and as 
cement is strengthened by iron wire and rods to give it tenacity 
under strain, so liquid asphalt can be treated for making tanks, 
pipes, conduits, reservoirs, etc. Asphalt, and india-rubber, of 
which it is a counterpart, are both hydro-carbons, having the 
same ingredients. Asphalt has little resisting power in itself, but 
it can be laid on a hempen sheet or thick paper, to give it more 
tenacity, as when laid upon a wood flooring. When liquid asphalt 
is used for the inside lining of a reservoir, vertically, a layer of 
brick should be laid in front of it as the work proceeds, to keep 
it up. In Germany, cement tanks for holding molasses are now 
being replaced by asphalt, which does not crack. Bitumen resists 
alkalies and acids, so that by mixing it with pure silex in powder, 
or with pulverized basalt, a mastic or paste can be made which 
can be applied like ordinary mastic for accumulator-rooms, baths 
for electrolysis, etc. ; numerous special applications of this material 
have been made for the Electric Traction Company at Paris, 
Lyons, and elsewhere. It has been found that the large Portland- 
cement-concrete blocks used in connection with breakwaters and 
piers to arrest the force of the waves, become disintegrated by the 
action of the magnesia in the sea-water, as well as by the boring 



ASPHALT INDUSTRY TO 1903. 83 

propensities of numerous marine animals. The blocks may be 
protected by an application of liquid asphalt, say 9-16 inch thick, 
upon each side of the cube, carefully jointed at the angles, and the 
remedy, though expensive, is sure. Asphalt flags are made by 
running mastic in shallow moulds on a true-planed cast-iron slab ; 
they are laid on a concrete base, the joints being run with a little 
special mastic, heated in an iron basin and spread with an iron 
tool. At the works of the Compagnie Generale des Asphaltes de 
France, the strong-room is made of bituminous concrete, and is 
absolutely fireproof. Pipes and tubes can be made for the carry- 
ing of telegraph, telephone or power-wires. Bitumen resists the 
corrosive action of acetylene-gas on iron pipes ; and in Paris, 
water-pipes are coated with a layer of mastic before being laid in 
the ground, thus preventing external corrosion. 

"The chief application of asphalt to which the Author desires 
to direct attention in this Paper, however, is its use as a material 
for absorbing vibration, either caused by the passage of trains and 
heavy vehicles, or by percussion, like that of the steam-hammer, 
and also as a foundation for heavy ordnance in forts. Mr. Malo, 
at the Seyssel mines, first experimented on these materials, and 
his lead has been followed up by the Author. The material used 
may be either bituminous concrete, or asphaltic powder, as used 
for roadways ; the powder, however, must be rammed in successive 
layers in a suitable case or box, made of steel or wrought iron, to, 
support and maintain it, and the layer, instead of being 2 inches 
thick, is 8 inches to 1 foot in thickness. Asphalt powder is used 
chiefly for foundations for steam-hammers, the bed-plate fitting on 
to the asphaltic mass. There are numerous examples of its use, 
and no failure has been recorded. In the year 1872 the Author 
had at work a Carr disintegrator, making 700 revolutions per 
minute, for grinding rock-asphalt, the axles being supported on 
stout oak bearings. The vibration transmitted through the soil was 
such that it was quite impossible to write within 600 feet of the 
machine. Being threatened with a lawsuit, he resolved to put 
down bituminous concrete foundations for the bearings, and to 
surround the pit in which the machine worked by a wall of the 
same material. When the work was completed, no one could tell 
in the adjoining workshops and warehouses whether the machine 
was working or not, and a glass of water placed on the bituminous 
concrete wall showed no ripples. For 30 years, during which at 



84 ASPHALTS. [chap. xii. 

least 5,000,000 tons of asphalt have een ground to fine powder, 
no repairs have been necessary. One of the more notable applica- 
tions was made by the Orleans Railway in their underground 
railway between the Place Denfert-Rochereau and the Port Royal, 
where the line oassed by the Paris Observatory. Admiral Mou- 
chez, who was then Chief of the Observatory, feared that his mer- 
cury bath for daylight observations would be shaken, and a foun- 
dation consisting of 633 cubic yards of bituminous concrete was 
therefore laid under the rails in 1894. The trains have run over 
it ever since, and no repairs have been found necessary. In the 
premises of the famous firm of Moet & Chandon, who keep a 
stock of 8,000,000 bottles of champagne in the cellars, it was 
feared that the machinery laid down for the electric lighting of 
their 8 miles of cellaring, would shake the wine, and in 1888 the 
author put down 21 cubic yards of bituminous concrete, with a 
most satisfactory result. In 1892, the machinery being increased, 
the author laid down an additional 17 cubic yards. In the au- 
thor's opinion, the vibration on the Central London Railway 
would be absolutely arrested by laying the rails on a foundation 
of bituminous concrete. Of course, the train service would have 
to be stopped, but a great deal might be done in the night at bad 
places. 

"For iron bridges over which, or under which, trains pass, 
this material is invaluable. Where a Portland-cement concrete 
will crack like mosaic, this material will stand. The author has 
proved this in many cases, notably at an iron tubular bridge over 
the Seine at Elbeuf; at the Pont de l'Aqueduc, in Paris; and at 
the railway bridge over the Ceinture, or Girdle Railway, at Cour- 
celles. At many forts around the French coast the very heavy 
pivot-guns are mounted on foundations of bituminous concrete, 
which absorbs the vibration produced by a heavy discharge. The 
author has also used a coating of asphalt mastic in the granite 
embrasures of forts to counteract the splintering caused by the 
impact of small shells. 

"During the Commune of Paris, in 1871, the works of the 
author's company at the Quai de Valmy were under fire, and bul- 
lets which struck a heap of asphalt powder were flattened out. 
This led to the coating of iron turrets with asphalt. The late 
General Boulanger, when Minister of War, arranged with the 
author to build a block of 390 cubic yards of bituminous concrete 




WORTHING, ENGLAND. 




HOVE. ENGLAND. 
SURFACED WITH SEYSSEL ROCK ASPHALT MACADAM. 



20 



'ASPHALTS' 



ASPHALT INDUSTRY TO 11H)3. 85 

at the Polygon of Bourgcs, to test the effect of melinite shell, 
similar blocks being made of Portland-cement concrete and hy- 
draulic lime concrete. The whole was surrounded by a wall of 
unmortared stones. Melinite shells, 4 feet 3 inches in length by 
I foot Ij4 inches in diameter, with chrome-steel points, were fired 
at these masses. The result was that the cement- and lime-con- 
crete blocks were pulverized; the bituminous concrete was not 
pulverized, but was torn asunder. 

"The chief asphalt mine in Europe is the Seyssel mine, the 
largest in France. It stretches from Seyssel to Bellegarde in the 
synclinal basin of the Rhone, which flows through the Depart- 
ment Ain on the east, and the Haute Savoie on the west. It is 
10 miles in length and a little more than 3 miles in width, and its 
superficial area is about 20 square miles. 

"The bitumen which binds the soft lime oolite in this mine to 
form asphalt must have impregnated the limestone in a state of 
vapor, as is proved by the smoky appearance in the unimpreg- 
nated rock at Seyssel. The occurrence of bitumen in Trinidad, 
Venezuela, Cuba, and Mexico, on the surface of the earth, in its 
viscous state, just as it can be extracted from asphalt rock, would 
therefore appear to be due to the bituminous vapors having, at 
some depth, met with some porous rock like sandstone, through 
which they filtered upwards. 

"In Europe, the country that has taken the lead in laying 
compressed asphalt undoubtedly is Germany. There is more 
compressed asphalt paving in Berlin than in England and France 
together, there being about 2*^ million square yards, all laid oa 
Portland-cement concrete, 8 inches in thickness. These magnifi- 
cent roadways are one of the features of Berlin, and give it an 
aspect of brightness and cleanliness unknown to other European 
towns. The Germans have studied asphalt synthetically, and 
have produced sundry imitations. An artificial asphalt, composed 
of limestone and bitumen, introduced by Professor Dietrich, of 
Berlin, was laid in Konig-strasse, Berlin, but was afterwards re- 
placed; a mixture of Vorwohle asphalt and bitumen is used to a 
considerable extent. These mixtures are, perhaps, cheaper than 
natural asphalt, since, being made on the spot, the cost of railway 
carriage from the mines is eliminated; but they are inferior to 
natural asphalt, and with heavy traffic the surface has to be fre- 
quently repaired. German contractors have followed the English 



86 ASPHALTS. [chap. xn. 

lead, and have bought mines in Chieti in the Abruzzi, in Italy, 
and in Venezuela. 

"In conclusion, the author is of opinion that English munici- 
palities can borrow money so cheaply that it is not worth while 
to forego the advantages of hygienic streets, in asphalt, liquid 
and compressed." 



Chapter XIII. 
ASPHALTS IN 1908. 

ABOUT five years have elapsed since the foregoing chapters 
were published*. During this semi-decade the increase in 
the asphalt sources of production has grown by leaps and bounds. 
Their utilization has also found numerous new channels in the 
latest construction improvements of this twentieth century. Un- 
questionably the most important development is in the Texas 
asphalt refineries. In 1905 the author wrote for "Mineral Indus- 
try," Vol. 13, published by the Mining and Engineering Journal, 
as follows : 

"In 1903 considerable strides were made towards bringing 
Texas maltha and asphalts into prominence, and in 1904 the pro- 
duction was certainly more than that of California in 1902. The 
Texas asphalts are the residuum of heavy asphalt oils, similar in 
character to the California malthas, but with slightly different 
chemical properties. These asphalts have not been used for pav- 
ing without mixture with other asphalts, and have therefore not 
attracted the attention given to California products. It is said, 
however, that Texas maltha has very generally taken the place of 
California maltha as the fluxing material used with the harder 
asphalts for sheet asphalt pavements throughout the country east 
of the Mississippi River. This maltha has been extensively used 
in manufacturing artificial bitumens, and it has been used in con- 
junction with Cuban hard asphalt, Trinidad manjak, gilsonite and 
other asphalts requiring large amounts of softening material to 
give them pliability. 

The production in 1904 has been estimated at from 25,000 to 
30,000 tons. A large refinery was operated at Marcus Hook, 
near Philadelphia, but exact statistics of production there and in 
Texas are not available." 



♦They appeared in a series of twelve monthly issues in the "Architects 
and Builders Magazine." 



88 



ASPHALTS. 



[chap. xiii. 



The trouble then experienced in obtaining full data on this 
subject continues to exist, but from the fact that the Gulf Re- 
fining Co. produced in 1907 over 25,000 tons one gets the most 
astonishing fact, that should the production of the Texas Co. 
and the Sun Co. have been in the same ratio, the result would be 
about 75,000 tons of material, which, on a basis of 99 per cent, 
pure bitumen, would equal 150,000 tons of crude Trinidad asphalt, 
that material losing 30 per cent, in refining and the refined ma- 
terial yielding only about 54 per cent, of bitumen. 

The methods of refining appear to be different among the 
companies named. The "Texaco" for instance, shows in the 
penetration test the following comparisons with other well-known 
asphalts : 



MECHANICAL ANALYSES ;- 
showing the stability of standard 

asphaltic cements 
Giving the softness (penetration) 
at atmospheric temperatures 

FROM 

THE TEXAS C 

NEW YORK 



!// 




./, 



The refining of Boorman's Noflux asphalt yields a material 
giving practically the same results in the penetration. This ma- 
terial is sold for fluxing European rock asphalt mastics and for 
tise in Malthalithic sidewalks and roads, as well as in the standard 
sheet asphalt pavements. 



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'ASPHALTS' 



ASPHALTS IN 1008. 89 

The uses to which these asphalts have been put are varied, 
and to a great extent, they have been used for blending with hard 
or glance pitch asphalts for different classes of work, and exten- 
sively for water proofing and insulating and in the manufacture 
of roofing felts and prepared roofings. One of the latest applica- 
tions of this material seen by the writer was in the laying of the 
pavement of Springdale Ave., between Roseville Ave. and 13th 
St., Newark, N. J., where a two and one-half inch asphalt con- 
crete of Texaco asphalt was applied on a 6-inch Portland-cement 
concrete base with gratifying results. 

The Texas liquid asphalts have entered largely in what is 
termed "blended asphalts," one of which is the Dunderberg as- 
phalt, a blending of Trinidad manjak or glance pitch with liquid 
Texas, the Dunderberg Asphalt Co. of New York having a plant 
at Jones' Point, on the Hudson, where the material is refined. 
The Barber Asphalt Paving Co. also manufacture the "blended 
asphalts," and other companies refine hard asphalts on similar 
lines. 

Among the best qualities of California asphalt is that refined 
for the Warren Asphalt Paving Co., known as Acme Asphalt. 
The specifications read as follows : 

"Acme" Asphalt Paving Cement. — The cementing material, 
or paving cement, shall be prepared from the best quality of pure 
"Acme" refined asphaltum mixed and thoroughly agitated with 
"Acme" asphalt flux and unmixed with any of the products of 
coal tar or inferior bituminous products. 

The asphalt must be absolutely unaffected by water and suc- 
cessuflly withstand the following tests : 

(a) Paint a glass slid ewith a very thin film of the asphalt 
cement. 

(b) Make a briquette of sand heated to about 250 degrees 
Fahrenheit, all of which will pass a No. 20 and none pass a No. 30 
screen, mixed with hot asphalt cement in the proportions by 
weight of one part of melted asphalt to nine parts of sand, and 
press into a briquette, such as is used for testing hydraulic cement 
or other convenient mould. Immerse the asphalt-coated glass 
and the briquette in water at a temperature of 70 degrees to 90 
degrees Fahrenheit, so that a part of the asphalt is below and 
part above the water. Daily renew water lost by evaporation. If 
under either of these tests the asphalt near or below the surface 



90 



ASPHALTS. [chap. xiii. 



of the water turns a brownish color and has a disintegrated ap- 
pearance, or an odor of decay, it wiill be rejected. 

Trinidad Lake Asphalt will clearly show deterioration by 
this test within a week, and other inferior asphalts in a somewhat 
longer time. 

Binder Course. — On the concrete foundation prepared and 
laid as above shall be laid a binder course, which, after compres- 
sion with a steam roller, shall have a thickness of one (i) inch. 
The binder course shall be made of crushed stone or gravel, all 
of which shall be of such size as will pass a screen having one (i) 
inch openings, which, after heating to about 250 degrees Fahren- 
heit, shall be mixed with "ACME" asphalt paving cement in such 
proportions as will thoroughly coat every particle of stone. 

Wearing Surface. — The wearing surface shall be composed 
of- 

"Acme" asphalt cement (pure bitumen) from.. 9 to 11 per cent. 

Sand 88 to 79 per cent. 

Pulverized carbonate of lime 3 to 10 per cent. 

In order to make the pavement homogeneous, the propor- 
tion of asphaltic cement must be varied according to quality and 
character of the sand. The carbonate of lime may be reduced or 
omitted entirely when suitable sand can be obtained. The sand 
and asphaltic cement will be heated separately to about 300 de- 
grees Fahrenheit. The pulverized carbonate of lime shall be 
mixed with the hot sand in the required proportions, and then 
mixed with the hot sand in the required proportions, and then 
mixed with the asphaltic cement at the required temperature, and 
in the proper proportions, in a suitable apparatus, which will ef- 
fect a thorough mixture. The pavement mixture, prepared in the 
manner thus indicated, will be laid on the binder in one coat; it 
will be brought to the ground in carts or wagons, at a tempera- 
ture of about 250 degrees Fahrenheit; it will then be carefully 
spread by means of hot iron rakes on the binder, in such manner 
as to give a uniform and regular grade, and to such depth that, 
after having received its ultimate compression, it will have a thick- 
ness of one and one-half (1^2) inches or two (2) inches, as the 
traffic conditions may demand and as the engineer may specify. 
The surface will then be slightly compressed by light hand or 



ASPHALTS IN 1908. 9 1 

steam roller, after which a small amount of hydraulic cement will 
be swept over it, and it will then be thoroughly compressed by a 
steam roller of at least five (5) tons' weight, the rolling being con- 
tinued as long as it makes an impression on the surface. 

During the past three years the city of Winnipeg has pur- 
chased Acme asphalt and has laid 37,000 square yards on its lead- 
ing thoroughfares. 

This city, under the direction of Mayors Andrews and Arbuth- 
not and City Engineer Col. H. N. Ruttan, bears the important 
distinction of being the first municipality to organize and success- 
fully carry out the laying of asphalt pavements by the direct pur- 
chase of all the materials and employment of labor without the 
intervention of paving contractors. The results which have been 
published show that this has been a very great success both in 
character and economy of construction. It is very evident that 
the city has done the work in the most economical manner and 
that it has saved not only the contractor's profit, but the cost of 
bonds and other expenses of organization, etc., to which a con- 
tractor is subjected and which add very materially to the con- 
tractor's cost. 

The city purchased a complete asphalt paving plant. The 
work was done under the general supervision of Colonel Ruttan, 
City Engineer. The asphalt construction of the work has been 
done during the past three years under the immediate efficient 
supervision and expert advice of Mr. F. E. Puffer, of Newark, 
New Jersey, and formerly Superintendent of the Warren-Scharf 
Asphalt Paving Company. 



Chapter XIV. 
ASPHALT IN BUILDING CONSTRUCTION.* 

ASPHALT is a material that has received but little considera- 
tion at the hands of engineers and architects. When even 
in Paris, the city of asphalt, the paper announced during the siege 
of that city that "If the besieged lacked bread, they were, at least, 
not likely to lack combustibles, for they could burn the asphalt 
w?hich was in their streets," it is not surprising that elsewhere the 
information as to the properties of th ematerial should be of a 
meagre character. Lately asphalt has been more fully discussed 
in its relation to street pavements. In this direction I will not 
trespass upon your time this evening, but will confine myself to 
its use in the construction of buildings. Asphaltos is an ancient 
Greek word which passed into the Latin as asphaltum. The Eng- 
lish word asphalt is applied to the bituminous limestones or the 
bituminous pitch which are commonly known as "natural as- 
phalts." From the earliest days we hear of asphalt, and in the 
book of Genesis we read of its use both in the Tower of Babel 
and in the construction of the ark. It is said that th ewalls of 
Babylon were cemented with asphalt, and evidences still exist of 
its use by the Egyptians. The first treatise on asphalt aws pub- 
lished in 1721, having been written by Eyrini d'Eyrinis, "Professor 
of Greek, Doctor of Medicine," and treated in a half serious, half 
humorous manner of its uses for building purposes, claiming it 
as a -panacea for almost every sickness. This curious pamphlet 
was reproduced in one of the publications of Mr. Leon Malo, 
C. E., of Paris, whose works on asphalt pavements are the most 
practical and scientific of any written on the subject. While the 
claims of the eccentric doctor that its use would stop the gout, 
cure children's chilblains, etc., appear ridiculous, the sanitary ben- 
efits of the introduction of the material are undoubted, and the 
good effects of inhaling the smoke of the hot material is evi- 



*Paper read before the Architectural Students' League of Brooklyn 
May 14th, 1890, by Mr. T. H. Boorman, of New York. 




WEST STREET BUILDING, NEW YORK. 
Waterproofing done by The Sicilian Asphalt Paving Company. 



22 



"ASPHALTS' 



ASPHALTS IN BUILDING CONSTRUCTION. 93 

denced by the rugged health of the men who are engaged in lay- 
ing it, and I may also mention that at the time the yellow fever 
raged in Memphis a few years since, it was proposed to burn as- 
phalt in the streets to prevent contagion and kill the fever germs. 
In 1834 M. de Puvis, in the "Annales des Mines," gave particulars 
of the manufacture of asphalt mastic at Pyrimont, and recorded 
the confidence already felt in that mastic used for footpaths at 
Lyons. The first asphalt work that I know of being laid in this 
country was about the year 1838, on the floors of the portico of 
the old Philadelphia Merchants' Exchange. 

Twenty-five or thirty years ago the European asphalts were 
extensively imported, at a great expense by our Government for 
use on fortifications in covering the arches over casemates, maga- 
zines, vaults and for other similar purposes. Since 1872 they have 
been imported by asphalt companies and used in buildings of all 
descriptions. 

Rock asphalt is a lime ore impregnated naturally by a geo- 
logical phenomenon, still but imperfectly explanied, with bitumen 
in the proportion of 8 to 17 for 100. It is found in strata like coal. 
The principal mines are the Limmer, near Hanover, Germany, the 
Neuchatel in Switzerland, and the Seyssel in France. For street 
work, the mines at Ragusa, Sicily, produce a rock, rich in bitu- 
men, which has been used in New York and other American cities 
with great success. On the coast of California, near Santa Bar- 
bara, and also in certain portions of Kentucky, Colorado, Utah 
and New Mexico, are found large beds of sandstone containing 
from 15 per cent, to 20 per cent, of bitumen. Recently this ma- 
terial has been used for paving in cities on the Pacific coast. 

For use in buildings the natural rock is manufactured into 
what is known as asphalt mastic in the following manner : 

The rock, after being reduced to powder, is placed in cylin- 
drical kettles, in which about 8 per cent, of Trinidad asphalt has 
previously been placed and melted. The mass is stirred by re- 
volving arms and agitators, at a temperature of about 350 F., 
for about five hours. It is thus thoroughly "cooked," and is then 
run out of the kettles into moulds, where it cools in the form of 
cakes or blocks, weighing from 50 to 60 pounds each. These are 
stamped wit hthe brands of th emines and imported into this 
country. The mastic so prepared shows an analysis, according 
to a report on Limmer blocks, manufactured by "The United 



94 ASPHALTS. [chap. xiv. 

Limmer & Vorwohle Rock Asphalt Co., Ltd.," prepared for the 
Department of Public Works, Philadelphia, by Dr. Charles M. 
Cresson, as follows: 

Bitumen 14.30 per cent. 

Carbonate of lime 85.20 " 

Silica, alumina and oxide of iron 50 " 



100.00 
To use it for walks or floors the material is again heated in 
suitable kettles in the following proportions : 

Mastic blocks (broken) 60 lbs. 

Trinidad asphalt 4 " 

Fine gravel and sand 36 " 



100 " 

This is "cooked" for about five hours at a temperature of 
about 400 F., great care being taken constantly to stir the mix- 
ture. It is then taken out of the kettle by th ebucketful and 
poured on the foundation prepared, its consistency being such 
that it will flow very slowly. It is then spread by means of wooden 
trowels, and compressed and smoothed by rubbing, as in plas- 
tering. 

Sidewalks so laid on concrete foundations have given great 
satisfaction in Paris, and are almost exclusively used throughout 
that city. Their superficial area is nearly 5,000,000 square yards, 
and their length probably exceeds 1,000 miles. 

In London, Berlin and Hanover, also, sidewalks of this ma- 
terial are used very extensively — in the latter city almost entirely. 

Having thus briefly described the preparation of asphalt 
mastic, I will now speak of its uses. From the cellar to the roof, 
asphalt has been used where the requirements have been water 
and fireproof floors. Its principal merits are its utter impervious- 
ness to water or damp, and its elasticity, whereby cracking, espe- 
cially from the influence of frost, is prevented. Also from a sani- 
tary point of view the advantages of asphalt are incontestable, for 
it possesses great antiseptic properties, and owing to its having 
no joints it is impossible for particle of animal or vegetable matter 
to lodge in crevices and putrefy. It greatly promotes cleanliness, 
as it can be easily washed, and for this reason is invaluable in hos- 
pitals, breweries, stables, etc. 



ASPHALTS IN BUILDING CONSTRUCTION. 95 

Asphalt first appears in your specifications as under the item 
of "Damp Course." It is advisable to lay throughout the walls 
on the grade of the cellar floor half an inch of asphalt, with a lap 
of about two inches on the inside, so allowing a connection with 
the asphalt finish of the cellar floor and hermetically sealing the 
house from damp, noxious gases and vermin.* 

In residences you will probably consider you have done your 
duty by asphalt if you have thus specified for your damp course 
and cellar floor, in the latter by the way, three-fourths of an inch 
of asphalt on three inches of hydraulic cement concrete will serve 
the desired purpose of a durable damp-proof floor. 

The yards of city residences are now frequently laid with 
asphalt, the material being peculiarly adapted to the roller-skates 
and tricycles of the younger members of a family. 

From a building then, in which only one floor, the cellar, is 
required to be of asphalt, let us consider where every floor and 
the roof can be of this material ; in printing houses, lithographing 
establishments, breweries, sugar refineries and slaughter houses, 
you will often find this material used throughout. This year, 
however, sees a novelty in construction with asphalt. Theophilus 
P. Chandler, Jr., architect, of Philadelphia, is using rock asphalt 
on every floor of a large apartment house ; the carpets will lay on 
the asphalt being fastened down to narrow strips of wood set 
against the partitions when the asphalt is laid. Now, I fancy I 
hear you say, "Well, asphalt is not pleasant in appearance." Why, 
gentlemen, the Mayor's private office in the great City Buildings 
of Philadelphia, the greatest municipal edifice in the country, is 
laid with asphalt with a border of colored tiles. 

Your association I am especially pleased to address tonight, 
for the reason that I find you wish to listen to practical papers; 
while so many of you are favorably known as artists with your 
pencils, you still are disposed to look thoroughly into the more pro- 
saic details of your profession. 

The "House Beautiful" must also be the "Home Healthy," 
and while the people delight in the beauties of architecture 
evolved from your pencils, they also wish to know that light, heat, 



*In connection with this use of asphalt mastic I was informed recently hy 
Mr. J. T. Brumshagen, of Baltimore, that in 1860 the building laws of German 
cities at that time insisted on a damp-proof course in every building and would 
allow of the use of nothing but rock asphalt for that purpose. 



96 ASPHALTS. [chap. xiv. 

ventilation and sanitation have not been neglected in your plans. 
This you realize, and in this is your strength. 

These remarks are intended to obtain your indulgence, while 
I venture to make a few suggestions as to methods of drawing 
specifications for asphalt work gleaned during eighteen years of 
study and prosecuting such work, including two years' experience 
as asphalt expert for the Department of Public Works and for 
the Department of Public Parks of New York city. 

For sidewalks and courtyards I would recommend one inch 
of rock asphalt on four inches of Portland cement concrete, made 
with the usual proportions of cement, stone and sand. For cellar 
floors and floors not subjected to much wear three-fourths of an 
inch of Limmer or other standard brand of mastic will suffice. 
For floors of breweries, stables, slaughter houses, sugar refineries, 
one inch is requisite. For ordinary hospital floors three-fourths 
of an inch thickness will suffice. For the roofs of fireproof build- 
ings on the top of concrete I would recommend an inch and a 
quarter of rock asphalt, in two coats, laid on three thicknesses 
of felt paper, cemented with Trinidad asphalt cement or bitumen. 

This bitumen is refined Trinidad asphalt which, after a treat- 
ment with petroleum residuum, forms an asphaltic cement which 
can be used with good effect for the coating of walls where they 
come in contact with the earth. I have seen specifications for 
the coating of walls with rock asphalt, but the weight of that 
material is a drawback to its application vertically, and for this 
purpose and for covering vaults and arches the Trinidad asphalt 
can be advantageously used. In cases where expense is no ob- 
ject I would say that the rock asphalt can be used vertically, but 
the work is expensive and tedious. I must not omit to call your 
attention to asphaltic masonry for engine beds. 

Of the use of asphalt in foundations, two very interesting 
examples are given by W. H. Delano, in a paper read before the 
English Institute of Civil Engineers in 1880. One was the foun- 
dation of a rock-disintegrator, running at a high rate of speed. It 
was first built upon a foundation of ordinary concrete. On the 
opposite side of the street was an establishment for painting on 
glass and china, where fine grades of work were required. The 
vibrations from the disintegrator were so great that the business 
of the glass painter was rendered impossible. He threatened suit 
for heavy damages, whereupon the foundations of the disinte- 



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23 



'ASPHALTS' 



ASPHALTS IN BUILDING CONSTRUCTION. 97 

grator were removed and rebuilt in asphalt concrete. The result 
was entirely successful, the vibrations becoming imperceptible. 
The second case was the foundation of a large trip-hammer, 
weighing forty-five tons, which was erected at the Paris Exposi- 
tion of 1867. In order to reduce the concussion, this was built 
in asphalt concrete, and with entire success. At the close of the 
Exposition, the concrete was so tough that it was found impos- 
sible to make an impression on it with a pick or chisel. As blast- 
ing was not permitted, the foundation had to be left in position, 
and it may be still there. 

In these cases the concrete was made from rock asphalt 
mastic. The proportions were 60 per cent, of broken stone and 
40 of gritted asphalt mastic. It was tamped between wooden 
frames, secured by iron cross-bolts, and these bolts were left in 
the material. 

In closing I would impress on you that the use of asphalt 
has been militated against not only by the lack of general knowl- 
edge of the material but by the failure of coal tar products which, 
under the name of "asphaltic cement," have led the public to con-' 
demn the legitimate article. As you do not expect to find the 
golden balls of the pawnbroker to be gold, neither must you 
expect to have natural rock asphalt used in your buildings if you 
specify for "asphaltic cement." 



Chapter XV. 
DUSTLESS ROADS. 

WHEN in England in 1904 the writer became interested in 
the laying of dust on macadam roads, and found in New- 
ark, Nottingham, the application of "Westrumite." 

This is a patented chemical preparation used in the making 
of roads and for laying the dust in roads, streets and open spaces, 
and is composed of oily substances rendered oluble in water by 
certain patented chemical and mechanical processes. 

Until the advent of "Westrumite" there were said to be only 
three agents which could la yany claim to consideration as pos- 
sible dust-layers, although none of them offered a true solution of 
the dust problem. These were water, tar and crude oil. 

Since then the author has investigated other temporary ap- 
plications, for relief from the disastrous effects of dust which, 
since the advent of the automobile, as a regular conveyance and 
not a luxury, has proved a menace to the health as well as the 
comfort of the residents and pedestrians on our macadam roads. 

There are many temporary allayments which might be men- 
tioned, but in all of which asphalt or liquid asphalt have little or 
no part, and so they are not considered in this book. 

In the year book of the Department of Agriculture for 1902, 
Col. James W. Abbott, then special agent, Rocky Mountain and 
Pacific Coast Division, Office of Public Road Inquiries, wrote 
that public attention was first called to the utility of crude petro- 
leum oil in road betterment through experiments made by the 
county of Los Angeles in California in 1898, where six miles of 
road were oiled in that year under the direction of the super- 
visors. The sole purpose of this work was to lay the dust, which, 
churned beneath the wheels of yearly increasing travel during the 



DUSTLESS ROADS. 99 

long dry seasons in that region, had become a most serious nui- 
sance. 

The following year this mileage was a little more than dou- 
bled in that county, and other counties in California also began 
experiments along the same line. 

From the very first the results obtained were so astonish- 
ingly successful that the practice rapidly increased. It spread 
through every county in Southern California, and then began to 
work north. Since then it has extended from near the Mexican 
line, on the south, to Durham, in Butte County, on the north, a 
stretch covering sections of quite widely differing climatic condi- 
tions, with an aggregate of about 750 miles of county roads and 
city streets oiled for one or more years. Oil has been used on the 
principal driveways of Golden Gate Park, San Francisco. The 
mountain stage road into the Yosemite National Park has been 
oiled for a distance of 30 miles, from its initial terminus at Ray- 
mond to eight miles above Wawona. In California it has long 
passed the experimental stage. 

In the California asphalts the asphaltene and petrolene are 
found combined in very variable proportions. In the petroleums 
which contain them the combinations of all the hydrocajjs^ns 
differ, not only in the same immediate oil field, but in the separate, 
strata and even in the same stratum. 

The very heaviest of the oils have almost the specific gravity? 
of water, while a naphtha may be 75 ° B., or even lighter. 

From the very beginning of the use of crude oil for roads irb 
California it seems to have been understood that it was the as- 
phalt in the oil which acted as the binder, and consequently they 
have always sought very heavy oils for that purpose. It might; 
naturally be supposed that the heavier the oil the greater the- 
percentage of asphalt. While this is approximately true, it does.. 
not necessarily follow. A crude oil is a complex mixture of light 
and heavy hydrocarbons, and its resultant gravity depends upon- 
the amount of each kind which it contains. 

Table VII. on the next page was compiled from the notes of 
eleven analyses of crude oils made in California by D. B. W. Alex- 
ander, now the Denver chemist of the Colorado Paving Company. 
The original determinations covered many other data, but in the 
table only the degrees Baume and the percentage of asphalt are 
shown : 



joo ASPHALTS. [chap. xv. 

All of these oils doubtless contained a small amount of min- 
eral matter which affected the specific gravity and disturbed the 
relation between it and the asphalt contained. 





Table VII. 




ANALYSES OI 


CRUDE 


OILS. 




Per cent. 




Per cent. 


"B. 


asphalt. 


' °B. 


asphalt. 


10.4 


64.1 


15-7 


39-9 


12.2 


" 45 


J 9 


28 


13 


61 


19.3 


32.8 


13-75 


59 


23 


254 


154 


32.1 


23 


43 


1 15.5 


50.2 







The above table shows that in selecting a petroleum for road 
purposes the specific gravity alone is not a sure guide. It also 
shows that the California practice of selecting a noil of 12 B. to 
14 B. can be depended upon for good results. 

Mr. L. B. De Camp, of San Francisco, suggests the follow- 
ing as a crude test used by him; it is probably closer than the 
-Baume measurement: 

Pour a definite amount of crude petroleum into a graduated 
glass and add an equal amount of refined petroleum. Stir thor- 
oughly together and add to the mixture 2 per cent, of commercial 
sulphuric acid. Again stir sthoroughly and the asphalt will pre- 
cipitate to the bottom. The percentage which it represents of the 
original amount of oil can be measured by the graduations on the 
glass. 

In California, where the aim is to always use an oil contain- 
ing as much asphalt as possible, the amount of oil required for a 
1 6- foot roadway varies between 250 and 400 barrels of 42 gallons 
each to the mile. This depends upon the thickness of the oil crust 
made, the porosity of the material, and the percentage of asphalt in 
the oil. 

The quicker this oil crust is made the better. If two applica- 
tions are made to a porous material and the oil properly stirred in 
each time, the crust will be finished. If the hard material is a 
clay, it should have at least two treatments. One will be sufficient 
for macadam. A dusty clay will require some gravel added for 
the first application. On the second application the crust which 
has begun to form should not be disturbed, but after all the oil 




THE HOTEL KNICKERBOCKER, NEW YORK. 

Waterproofing by The Union Construction & Waterproofing Company 

of New York. 



24 



"ASPHALTS' 



DUSTLESS ROADS. 101 

sinks in that will a layer of sand should be sprinkled on top. In 
this oiled crust the bottom will be made from the clay dust and 
the top mostly fro mthe added sand, while the middle will be a 
mixture of the two. 

In the first experiments a part of the oil was generally put 
on the first year, and the crust was completed the second or third 
year. The first year the thin crust was often broken through and 
a hole was left in the road. 

After the oiled crust has once been properly formed all the 
oil required will not exceed 25 barrels to the mile for repairs in 
each subsequent year. 

During the spring and summer of 1905 the Office of Public 
Roads cooperated with Mr. Sam C. Lancaster, city engineer of 
Jackson, Tenn., and chief engineer of the Madison County Good 
Roads Commission, in making a series of careful experiments at 
Jackson, Tenn. Tests were made of the utility of crude Texas 
oil and several grades of its residue when applied to earth and 
macadam roads. 

Seven tank cars of oil, given by some Texas and Louisiana 
companies, were used at Jackson. It varied in quality from a 
light, crude oil to a heavy, viscous residue from the refineries. 
Over seven miles of country road and several city streets were 
treated. 

At first, some of the lighter crude oils were applied with the 
same tank wagon that was used for the tar. Hose and brooms 
were used to spread the oil, and practically the same process was 
followed as with the tar. The oil soaked into the macadam very 
quickly and left on coating on top. It caused the light covering 
of sand which was applied to pack down and gave the road a dark 
color. 

It was soon noticed that the preliminary sweeping was un- 
necessary, as the roads were practically free from dust and oil 
would penetrate the surface. The removal of detritus was a loss 
to the road, which had to be replaced by sand to prevent excessive 
wear on the stone. It was later found that it was much cheaper 
to use an ordinary street sprinkler than the tank wagon, and in 
this case spreading the oil with brooms was unnecessary. 

The crude oil was used cold, and the cost 01 applying it by 
the different methods used is given below. 

On a city street 8,266 square yards were treated at the rate 



102 ASPHALTS. [chap. xv. 

of 0.48 of a gallon of oil per square yard with the use of the tank 
wagon and hose. The cost of labor per square yards was as 
follows : 

Sweeping street $0.0011 

Filling tank and hauling 0008 

Oiling street 0024 

Spreading sand 0014 

Total 0057 

On a country road 2,000 gallons were spread, covering 5,206 
square yards, at a rate of 0.38 of a gallon per square yard. The 
average haul was one mile. Only the manure was removed be- 
fore oiling. The cost of labor averaged $0.0033 P er square yard. 

It took nine men thirty minutes to spread 500 gallons, or one 
tank load, and the 18-foot road was covered at the rate of 1,860 
feet per hour. It took twenty-eight minutes to fill the tank car 
with oil. With an ordinary street sprinkler, one man and team 
spread one load of 600 gallons of oil in fifteen minutes. The 
sprinkler thus spread 600 gallons in one-half the time that it took 
nine men, with the tank wagon, to spread 500 gallons. 

The heavy residual oils were so thick when cold that they 
would not run through a 2-inch fire hose attached to the rear of 
the tank wagon, and it was necessary to pump the oil upon the 
road. The pump with which the tank was charged was used for 
this operation. Only one tank wagon (500 gallons) of the heavy 
oil was applied cold. It formed a thick, sticky mass on the top of 
the road that rolled about under pressure and seemed to have an 
unlimited capacity for absorbing the sand which was spread upon 
it. The street had to be cleared of the greater part of this mass 
of oil and sand within a short time. 

After this experience the oil was heated in the car by steam, 
and better results followed. It still ran slowly through the hose 
and nozzle, and it was found cheaper to take off the hose and 
allow the oil to flow from the outlet of the tank directly upon the 
road, where the men swept it over the surface with brooms. An 
air pump was tried, to increase the floflw of the tank by pressure, 
but the tank was not tight enough to prevent the escape of air, 
and this experiment was unsuccessful. 

Twenty-four hours after the application of the residual oil it 



DUSTLESS ROADS. 103 

was covered with sand or limestone screenings, and in four days it 
was firm enough to bear traffic without showing any wheel tracks. 
It shed the water well in a violent rain storm. 

The following was the cost per square yard of putting re- 
sidual oil on city streets with the use of the tank wagon. Ap- 
proximately 0.71 of a gallon of oil was used per square yard. 

Sweeping street $0.0010 

Heating, loading and hauling 0017 

Oiling street 0029 

Spreading sand 0022 

Total 0078 

Excellent results can be secured by the use of this heavy 
residual oil if it can be applied to the surface of the road at a 
temperature approaching the boiling point. 

The medium grade of oil, which was tried next, is classed by 
the refiners as "steamer oil." It wa sheavy enough to leave a 
slight coating on the surface, which made a very compact cover- 
ing with the dust of the road. Only the heavy matter was re- 
moved from the surface of the road before applying the oil. It 
was heated by steam in the car, but was not hot when it reached 
the road. It was not safe to build a fire in the tank wagon, and 
the best road surface was obtained where the oil was at the high- 
est temperature. Some method of heating the oil safely on the 
road would greatly improve the results. This could be accom- 
plished with a steam straction engine having steam coils con- 
nected with the tank, the engine hauling and heating the tank 
while spreading the oil. Most of this oil was applied with the 
street sprinkler, and it sprayed readily when hot. 

In applying the greater part of the oil on the country roads 
the following men and equipment were used: A foreman at $2 
per day; 6 laborers at $1.25 per day for working on the road and 
pumping oil at the car ; 1 tank wagon and 1 street sprinkler at $3 
each per day; 2 firemen at $1.50 per day, and 1 ton of coal. This 
force spread in one day 3 tank wagons of 1,500 gallons and 3 
sprinkler tank loads of 1,800 gallons, making a total of 3,300 
gallons. 

No sweeping was done on the country roads except to re- 
move manure and to spread the oil where it was inclined to 



104 ASPHALTS. [chap. xv. 

puddle. No sand or other material was applied to the road after 
oiling. 

More than seven months have now elapsed since the work 
was done. The light crude oil has produced little if any perma- 
nent results. Te roads where it was applied are but slightly 
changed, and some dust arises on them from traffic. The only 
apparent result is a slightly darker collore on the "shoulders" of 
the road, and but little difference can be noticed between this and 
other sections of the road which were not treated. This oil was 
too volatile for the purpose, and where it has to be shipped for 
any distance does not justify the expense of using it. 

The medium "steamer oil" fro mTexas has given good re- 
sults. There is a thin surface coat of dust packed down that pro- 
tects the stone from the grind and pounding of traffic. This 
effect is very noticeable in driving over it. The harsh grinding 
noise of the wheels, which is pronounced on the novaculite sur- 
face, disappears at once, and there is decided relief in driving 
'upon it. It is practically noiseless. This coating is perhaps one- 
eighth of an inch thick, and is not a concrete, but compacted 
dust, which is made to cohere by the oil with which it is saturated. 
This road does not wash or "pick up," and the wear on the rock 
is much decreased. 

A good macadam road forms a wearing coat of fine material, 
which is ncessary to its existence. If this coat is removed, an- 
other is formed and the life of the road is gauged by the rapidity 
with which the detritus is removed from the surface. The more 
rapidly it is removed the shorter will be the life of the road. The 
important result of applying the "steamer oil" was that the wear- 
ing cost was fixed and held to the surface, consequently the life 
of the road will be much greater. Of course some of it has blown 
and washed away, but it is perhaps safe to say that the loss is 
decreased by at least 75 per cent. 

The best results were obtained with the heavier oils when 
the oil was hot. The road treated with the heaviest oil is entirely 
dustless. Teams passing from the bare macadam upon the oiled 
road show this, for the cloud of dust behind a wagon dissapears at 
once, and the oiled roads can be cleaned or swept as well as the 
tarred roads. There is but little noise even from the horses' 
hoofs. 

Another experiment was tried of treating an ordinary earth 




25 



'ASPHALTS' 



DUSTLESS ROADS. 105 

road with the heavy oil after it had been shaped and graded. The 
soil was composed largely of sand and the oil was harrowed into 
it and the road rolled. This piece of road has become fairly 
smooth and firm enough to bear traffic. It is not hard like mac- 
adam and has small wheel marks. It is about as good as the usual 
earth road where the soil packs well in fair weather. It is an im- 
provement on the old road, as the sandy soil was cut into ruts, 
but it can hardly be recommended for use where the oil has to 
be shipped a great distance and is high in price. 

The experiments outlined above were in the main successful. 

Another series of experiments was conducted in 1907 by the 
Office of Public Roads at Bowling Green, Ky. The materials 
used were Kentucky rock asphalt tested for its fitness as a binder 
in macadam construction, crude Kentucky oil, and a special prep- 
aration of residuum oils, the last two of which were used as dust 
preventives. This work was done in cooperation with the au- 
thorities of Warren County and lay just beyond the city limits 
of Bowling Green. The location of each section of experimental 
work is given in connection with its description. 

The rock asphalt used in this experiment is a natural product 
formed in the Chester group of subcarboniferous rocks over a 
course extending through Breckinridge, Grayson, Edmonson, 
Logan, and Warren counties in Kentucky, marking the edge of 
the coal fields lying in the wesetrn part of that State. It is fine- 
grained sandstone which in the past has been impregnated with 
mineral pitch or bitumen, the latter averaging from 6 to 8 per 
cent, with a maximum of 12 per cent. Both appearance and im- 
pregnation are irregular, for it is generally found in pockets rather 
than in distinct continuous veins, and the distribution of the bitu- 
men over the pocket ranges from a mere trace to saturation. 

The quarrying and first crushing of rock asphalt are not un- 
like that of other rock intended for macadam or concrete work. 
After having been broken into pieces to pass through a 2-inch 
ring, it is conducted to a series of roll crushers, consisting of 
parallel steel cylinders. The bitumen in the rock gives sufficient 
adehsion to carry the material through the rolls, once it has been 
forced against them. The finished product after crushing is a 
mass of individual grains of sand, each thoroughly coated with a 
film of mineral pitch sujciently glutinous to cause it to adhere to 
surrounding grains and to pack very firmly if subjected to pres- 



106 ASPHALTS. [CHAP. XV. 

sure. If chilled when compacted, a lump becomes very hard and 
tough ; if warmed in the hand, the bitumen becomes soft and semi- 
fluid and the individual grains of sand fall from the mass of their 
own weight. When freshly crushed it is of rich dark brown color 
with a slight lustre which gradually disappears as the bitumen 
hardens and dries. 

The test was made on what is known as Cemetery pike, run- 
ning east from the city limits of Bowling Green. It is the main 
thoroughfare leading from the southern and eastern parts of 
Warren County to Bowling Green, the county seat, and, besides 
being the route for heavy rural traffic, it passes extensive gravel 
beds and timber lands from which heavy loads are being con- 
stantly taken on narrow tires. 

The form of construction origianlly adopted was a 20-foot 
Telford road. When this surface had been worn away under 
traffic and the foundation exposed it was repaired and brought 
to grade with a sharp gravel containing about 20 per cent, of 
sand and clay. This bed of gravel was about 8 inches thick, com- 
pacted. Previously to the experiments it was loosened to a depth 
of four inches by means of a spiked roller and a heavy harrow, 
and was shoveled out by hand. The subgrade was then made to 
conform to the crown of the roadway, which was planned to be 
4j4 inches in 9 feet, or an average of one-half inch per foot. The 
gravel removed in shaping the subgrade was used for repairs on 
the roadway beyond the work. 

After thoroughly compacting the subgrade with a roller the 
wearing course of stone was laid. It consisted of limestone 
crushed to range from 1 inch to iy 2 inches in largest dimension 
and was spread to a uniform depth of 4 inches. This course was 
then rolled once to turn down the sharp edges of the stone and 
form a smooth, even surface. No further attempt was made to 
reduce the voids in the stone by compacting it, as these were to 
be filled with the rock asphalt. This material was then thrown 
on with shovels from wagons and dumping boards along one side 
of the road. It was spread to a depth of iy 2 inches, care being 
taken to break all lumps and to work all the asphalt rock possible 
into the interstices of the stone without disturbing the latter. 

As the work progressed the roller was kept moving back and 
forth parallel to the axis of the roadway and was worked from 
the outer edge to the crown as in ordinary macadam construe- 



DUSTLESS ROADS. 107 

tion. To prevent the adhesion of the bitumen to the wheels of 
the roller a light coating of natural cement was dusted over the 
rock asphalt, but it was soon found that in moving the roller off 
the work at the end of each rolling enough dust collected on the 
wheels to prevent adhesion and no more cement was used. The 
stone had not been thoroughly compacted before applying the 
asphalt, and for this reason a very perceptible wave in the surface 
preceded the roller, causing the asphalt to crack until after the 
fourth or fifth rolling. At this stage most of the coating had been 
forced into the voids of the stone, as was found by cutting into 
the surface, and very little decrease in its thickness was detected 
after the rock had come to a firm bearing. In this manner a sec- 
tion 385 feet long and 18 feet wide was paved. 

The behavior of the rock asphalt varied according to tem- 
perature. During early morning, when both asphalt and rock 
were cold, it worked into hard, rounded lumps, which were broken 
with difficulty with the rakes. The location of such lumps was 
plainly visible after repeated rolling, but they disappeared com- 
pletely after being subjected to the heat of the sun. As the day 
grew warmer the material spread smoothly and compacted evenly 
and uniformly. A light but cold rain, with temperature of 
65 ° F., impeded work for several hours. After a temperature 
of from 70 to 75 F. was reached work progressed well 
and good results were obtained immediately. The temperature 
of the days during the period covered by the work was uniform, 
excepting at the time of the cold rain mentioned above, with a 
maximum temperature ranging from 94 to 97 F. during the 
heat of the day. The inadvisability of working the material when 
chilled and damp was apparent, for that portion of the road laid 
at a temperature of 65 ° F. failed to become hard and firm for 
several hours after subsequent applications had compacted satis- 
factorily. 

One difficulty met in this work was caused by the necessity 
for having one-half of the roadway open to traffic, while the other 
half was under construction. In order to avoid a break or distinct 
line between the parts, the inner edge of the asphalt was rolled 
lightly, so that when the other half of the work was laid the loose 
particles would unite without difficulty. As a result of this pre- 
caution an unbroken surface along the middle of the roadway was 
secured. The ready cohesion of the particles was further shown 



108 ASPHALTS. [chap. XV. 

when, after an accident, it was necessary to repair a portion which 
had been opened to traffic for three days. The asphalt and stone 
were removed over an area of 4 square feet, the stone replaced 
and tamped by hand, and a new coating of asphalt applied and 
rolled. After two days no evidence of damage or repair remained 
visible. 

As soon as one-half of the roadway had been surfaced and 
properly rolled it was opened to traffic in the hope that the asphalt 
would be further worked into the voids of the stone by the action 
of wheels and hoofs. At first the coating rutted badly under the 
weight of the heavy loads of gravel and logs to which it was sub- 
jected and the smooth surface given by the roller was seriously 
cut by hoofs. This effect decreased visibly after three or four 
days ; at the end of a week no trace remained of the deepest ruts 
and the surface had become smooth and compact. It then pre- 
sented an appearance not unlike that of an asphalt pavement 
which has been open to traffic for some time. Close inspection, 
however, showed the presence of a slight excess of bitumen which 
held a thin film of dust and fine sand closely and caused it to be- 
come incorporated into the surface under traffic. With the pass- 
ing of time this excess of bitumen disappeared and at the end of 
four months very little was noticeable. 

The conditions necessary to satisfactory results from the use 
of rock asphalt in this form as a binder in macadam road con- 
struction are: That the broken stone of the wearing course be 
clean and dry to facilitate adhesion of the bitumen and of fairly 
uniform size and uncompacted to give a large percentage of 
voids; that the stone be spread evenly and true to grade; that 
the temperature of the atmosphere be sufficiently high to cause 
the bitumen to soften and allow the grains to glide over each 
other readily ; that the asphalt be thoroughly raked into the voids 
of the stone without disturbing the latter. 

The simplest method of rolling rock asphalt is to have the 
roller move forward as far as the work permits, returning with 
but little lateral change of course. Any great change in the 
course of the roller accompanied by rapid guiding movement of 
the trunnion roll causes the loose asphalt to slough over the stone 
surface and tends to make it adhere to the trunnion roll. For 
similar reasons sudden starting, stopping, and reversing are to 
be avoided until the material has been thoroughly compacted. If 




26 



'ASPHALTS' 



DUSTLESS ROADS. 109 

the roller is driven upon newly spread material a distance less 
than its wheel base, at the same time working from the outside 
to the crown of the road, the drive rolls may always be kept upon 
partially compacted material. In this manner the rolling may be 
kept abreast of the spreading, little damage being done in case 
of rain or sudden cold, and any defects in the work will become 
apparent as the work progresses. 

The stone, labor, teams, and roller were furnished by the 
county authorities. Labor ranged from $1.20 to $1.25 and teams 
cost $3 per day of ten hours. The roller was loaned to the county 
for this work and the cost of operating it was $2.50 per day for 
the engineer plus the cost of fuel. The water for the roller was 
taken free of charge from the city mains, but as a team was kept 
constantly to supply water and coal to the roller this amount is 
charged in the item of rolling. About 65 cubic yards of gravel 
was removed in shaping the subgrade and used to repair the 
gravel surface beyond the point where the work stopped. The 
cost of loading and hauling this material is charged against the 
asphalt work, while the spreading, rolling, and sprinkling of the 
gravel is charged against repair work in the preparation of the 
roadway to receive a treatment of oil. This item is referred to 
again in the discussion of the cost of experiments in the use of 
oil as a dust preventive. The unit cost of rolling is large in pro- 
portion to the actual cost of the roller to the county, by reason 
of the short length of road surfaced. As a consequence the roller 
was frequently idle, though under steam. 

Two factors lent themselves to increasing the cost of spread- 
ing the asphalt : The inexperience of the laborers in working the 
material, and the long haul to which it was subjected. The former 
would have been materially reduced after a few days, but the 
latter was unavoidable and resulted in packing the rock asphalt 
so firmly that it required great additional labor afterwards to 
break the lumps. The stone was delivered on the roadway at 
$1.20 per cubic yard and was spread 4 inches thick uncompacted, 
making the cost per square yard delivered 13 cents. The rock 
asphalt was donated, but is charged in the following table at its 
market price of $5 per ton f. o. b. cars at Bowling Green, and 
the cost of loading and hauling it is included in its unit cost de- 
livered on the work. It was spread about 1^2 inches thick, or at 
a rate of 24.5 square yards per ton. 



no 



ASPHALTS. [chap. xv. 



The following table contains an itemized statement of the 
cost of the various processes of the work: 

Table VIII. 

COST DATA OF ROCK ASPHALT EXPERIMENT. 

Cost 

per square Percentage 

Item. yard. Total cost. of total. 

Cents. Dollars. Per cent. 

Shaping subgrade 5.66 43 -6o 11.8 

Stone on work 13.71 105.60 28.8 

Spreading stone 78 5.97 1.7 

Rolling stone 09 .67 .3 

Asphalt on work 23.77 183.10 50.0 

Spreading asphalt 1.44 n.06^2 3.1 

Rolling asphalt 2.18 16.78^ 4.3 

Total 47.63 366.79 100.0 

As has already been stated, the finished road surface was 
similar to an asphalt pavement which had been open to traffic for 
some time in its dark-brown color and smooth even finish. Prac- 
tically little impression was made on the surface by traffic after 
a week, except on very warm days, and this was not sufficient to 
impair its appearance or value. Incisions into the surface re- 
vealed a dense coating of dust and sand about one-eighth of an 
inch in thickness thoroughly incorporated in the bitumen. This 
served at once as a wearing surface and as a protection to retain 
the bitumen in the sand below. Only at one or two points did 
the limestone of the wearing course protrude. This occurred 
where the rock had been disturbed after it had been rolled and 
had been forced up into the asphalt layer. Rolling and traffic 
had left it flush with the surface, however, and its presence was» 
considered as a defect in the appearance rather than in the wear- 
ing quality of the roadway. 

After four months the appearance of the roadway had under- 
gone no appreciable change. Along the crown a few more par- 
ticles of limestone were exposed to view. This was undoubtedly 
due in large measure to the effect of traffic in forcing the asphalt 



DUSTLESS ROADS. Ill 

into the voids of the stone, for a large part of the traffic is con- 
fined to the center of the pavement. This development was not 
regarded as of serious consequence, however, as the rock along 
the axis of the roadway had been more or less disturbed while 
the asphalt was being laid, and it is probable that the few pro- 
truding stones were those which had been raised above the gen- 
eral plane of the rock surface and were not covered to the same 
depth by the rock asphalt as surrounding rock. Incisions into 
the asphalt at this time revealed no perceptible loss by drying or 
hardening of the bitumen, as the sand particles showed their 
normal inclination to move when warmed in the hand. 

The permanence of macadam construction depends largely 
upon the nature of the binder used and the ability of traffic to 
supply by attrition the material which is removed by wind and 
water. It was to test the adaptability of rock asphalt as such 
binding material that this piece of construction was undertaken. 
The pavement formed is dustless. There is no appreciable wear 
of the surface material to be raised and carried away by the wind 
as dust and such dirt, as may be carried upon it is readily re- 
moved by sweeping or flushing with water. There is sufficient 
adhesive power in the bitumen to serve as a cement to hold the 
stone of the wearing course in place, giving at once a smooth and 
waterproof surface. It is resistant to deformation under a load, 
yet sufficiently plastic to break the severity of the blow from a 
horse's hoof, and thus, in a measure, avoids the harmful effects 
of rigid pavements on animals. 



Chapter XVI. 
METHODS OF SURFACING ROADS. 

STARTING with the more lasting and more substantial 
methods of waterproof surfacing of macadam roads, 
prominent mention must be made of the system which is the re- 
sult of two years' careful experiments and research made by 
George C. Clausen, of the Sicilian Asphalt Paving Co., formerly 
President of the Board of Park Commissioners in the halcyon 
days, when the office of Park Commissioner was not given as a 
"political plum." 

In the specifications of the Sicilian Asphalt Paving Co. for 
roadways for heavy automobile traffic, they first provide as the 
main supporting body a layer of good sized clean stones, free 
from all fine stuff, sand, or dirt. 

They roll this layer of clean stones until they are crowded 
firmly together and brought to an even surface. They then apply 
hot asphalt as a binder, filling the voids and overflowing the top 
of the layer to receive a coat of small stones which, when kneaded 
into the surplus asphalt, forms the wearing surface of the road. 

To knead the small stones into the asphalt without disturb- 
ing the under layer, they use a special heavy steam roller de- 
signed for that purpose. 

Their method of thoroughly rolling the bed of coarse stones 
before the asphalt binder is applied produces a strong and stiff 
under layer which cannot be displaced or flattened out by the 
traffic. This non-elastic base preserves the grade and crown of 
the surface layer which is anchored fast to it by the asphalt ex- 
tending through both layers. 

The surface of small stones and asphalt will always be elas- 
tic and therefore non-slippery. The wear is very little, the sur- 
face being cushioned by the asphalt. 

The roadway is dustless and waterproof and cannot be 
washed out or gullied by storms. It has its full strength and is 
ready for immediate use when laid. 




'ASPHALTS' 



SURFACING ROADS. 113 

It is preferred to use the ordinary commercial i^-inch stone 
for the under layer of the road, including stones passing a 2 l / 2 - 
inch ring and having all that will pass a ij4-inch ring screened 
out of it. For the surface, the part screened out can be used, pro- 
vided it is clean and free from dirt. 

Any good macadamized road has stone in it fit for the pur- 
pose and can be readily converted to this system, making it dust- 
less and automobile-proof at comparatively little expense. 

In August, 1906, there was put down for experimental pur- 
poses over 6,000 square yards of this roadway in Bronx Park, 
New York, near the eastern gate, where the automobile and 
other traffic is very heavy. It was put down of various thick- 
nesses, in some places very thin indeed and nowhere more than 
half the thickness called for in their present specifications. They 
used various compositions of asphalt by means of which they now 
claim to know exactly which is the best to use. 

After two years' use this roadway now stands the heaviest 
kind of automobile traffic with perfect success, and with remark- 
ably little wear. This example shows that the automobiles can- 
not strip the surface layer even if only a quarter of an inch thick; 
that the surface is non-slippery and dustless and though always 
altstic, that it never forms into waves or gets humpy, but keeps 
in perfect shape as to crown and grade. 

The under layer alone makes a good road and will carry the 
traffic for a long time if the road is neglected. Repairs can be 
made at any time without disturbing the surface. 

It will be seen that the construction of their roadway is 
simple and easily understood and that no well-established prin- 
ciple of roadmaking is violated. 

The specifications issued by this company are as follows: 

SPECIFICATION. 

The roadbed must be firm enough to be finished to sub-grade by a 10 
to 15-ton roller. 

The surface of the roadbed is to be six inches (6") below grade. It 
must be closely compact and of such a nature that the macadam cannot 
be pressed into it more than one inch (1") by a 10 to 15-ton roller. 

On this roadbed a layer of one and one-half inch (1%") stone is to be 
evenly spread to a depth of six inches (6"), more or less, as may be 
needed to bring the surface of the layer when finished to within two inches 
(2") of grade. 

The stones used in this layer must be clean and free from any fine 
stuff that would act as a binder. 



Il 4 ASPHALTS. [chap. XVI. 

It must be thoroughly rolled with a 10 to 15-ton roller until a firm, 
unbound surface is obtained, composed exclusively of good-sized stones 
crowded together, face up, in horizontal alignment. 

The aligned surface of the layer being carefully maintained, it is to 
be flooded with hot "Sicilian asphalto" of a quality as hereinafter specified, 
so it will flow into and fill all the interstices and voids and at the same 
time overflow and cover the surface of the layer to a depth not less than 
three-quarters (%) of an inch. 

The Sicilian Asphalto is a mixture of bituminous ingredients, carefully 
manipulated so as to make a soft and tough binder, without liquifying 
injuriously in hot weather. 

Hudson River Road Gravel, or a mixture of three-quarter inch (%") 
stone and screenings of Trap Rock must now be evenly spread upon the 
Asphalt, enough to be used to bring the surface of the road to grade when 
finished. 

This material must then be thoroughly kneaded into the Asphalt with- 
out disturbing the under layer, and rolled until a smooth, dustless, elastic 
surface is obtained. 

Another excellent device for surfacing macadam is that in- 
troduced by the Wadsworth Stone and Paving Company, pre- 
viously mentioned in the Public Roads Office reports, and is as 
follows : 

SPECIFICATION. 

The sub-grade will be brought to an even surface, parallel with the 
grade proposed for the pavement, by making the necessary excavation 
or embankment. Soft or spongy earth, or other material not affording a 
firm foundation, will be removed, and the space filled with sound stone, 
'which shall be solidified by ramming or rolling, as hereinafter provided. 
The sub-grade surface will be compacted by rolling with a roller operated 
by steam power and weighing not less than ten (10) tons. Any portion 
not accessible to roller shall be thoroughly compacted by ramming. When 
the rolling and ramming shall have been done, the surface shall be 
true and smooth and eight (8) inches below the proposed finished surface 
for the pavement. 

Upon the sub-grade thus prepared shall be spread an even layer of 
sound, hard limestone or furnace slag broken into fragments so that the 
largest diameter of any stone shall not be over 3". The stone or slag 
must be free from clay or dirt and contain no vegetable or perishable 
matter. This layer of stone or slag, after the same has been thoroughly 
rolled shall be 6" thick, and its surfaces shall be parallel with the 
finished contour of roadway and 2" below same. This layer of stone 
shall contain an even and uniform amount of screenings, equal to twenty- 
five (25) per cent, of the total amount of stone, so that the stone can be 
thoroughly compacted in rolling. This layer of stone, if the contractor 
sees fit, may be hauled upon the sub-grade, and there broken to the 
required size. 

Upon this layer of stone, prepared as described, there shall be evenly 
spread a layer of hard, sound, clean limestone, free from screenings, dust 
or dirt crushed into fragments varying uniformly in size from one and 
one-half (XV2") inches to two and one-half (2%") inches, measured on 
longest diameter. 



SURFACING ROADS. 115 

This last layer of crushed limestone after being uniformly spread, 
shall be rolled once. After said rolling, the top layer shal measure two 
(2) inches. Kentucky Rock Asphalt shall then be hauled on the street in 
carts or wheelbarrows and dumped, after which it shall be spread and 
raked with asphalt rakes, in manner satisfactory to the Engineer. This 
Kentucky Rock Asphalt shall be pulverized and shall contain not less 
then seven (7) per cent, of natural bitumen. This top surface shall then 
be thoroughly rolled until the interstices of the crushed stone are entirely 
filled with Rock Asphalt, and the surface of the roadway is hard and even, 
and entirely covered with Rock Asphalt; the whole to be satisfactory to 
the Engineer in charge. 

This work must be done in dry and warm weather, with the ther- 
mometer showing, not less, than 70 degrees F. If the Asphalt surface 
of the street should be damp or moist from any cause, it shall not be 
rolled until the sun has thoroughly dried the surface. Whenever, after 
one or more rollings, it is found that Rock Asphalt sticks to the roller, 
the surface of the street shall then be dusted with hydraulic cement to 
the satisfaction of the Engineer. 

The Rock Asphalt shall be so spread upon the street that one (1) ton of 
2,000 lbs. will cover, not more, than twenty-five (25) square yards. 

The Good Roads Improvement Co. have done work in sev- 
eral sections of the country, using a material known as Asphalt- 
oiline. This is made from crude oil with the heaviest natural 
asphaltum base of any oil west of California and contains no par- 
affine and no sulphur. It is treated and refined to eliminate the 
volatile matters and other constituents and is a liquid asphalt 
from 75% to 95% pure, according to grades, and contains suffi- 
cient petroleum to secure proper penetration. 

Their formula is as follows: 

After the road is finished according to specifications for 
macadamizing to the entire satisfaction of your engineer we 
agree to put on a coat of liquid asphalt oil to be applied accord- 
ing to the following : 

SPECIFICATION. 

The prepared roadbed shall be treated by distributing the liquid 
asphalt oil over the surface of the same, at the rate of not less than 
% gallon per square yard by means of a machine fitted with an ap- 
pliance for the purpose and so arranged as to enable the operator to 
control the flow and distribute the material equally and uniformly, leaving 
no streaks or spots, and also enable the operator to cut out any part or 
section to avoid depositing a surplus of the material on the roadway or 
on railway tracks (if such are located in the roadway), or in the gutters, 
and to completely control the quantity delivered. 

A coat of 50 per cent, %-inch stone and 50 per cent, screenings 
properly mixed is spread to a sufficient thickness to a smooth and 
uniform surface to the road, then again rolled until the road becomes 
thoroughly consolidated, hard and smooth. Any depressions formed 



n6 ASPHALTS. [chap. xvi. 

during rolling or from any other cause are to be filled in with 1%-inch 
stone and screening brought to the proper road grade and curvature as 
determined by the Engineer. 

The Indian Refining Co. sell a blended liquid asphalt from 
Kentucky — a manufactured product carrying 75 per cent, asphalt 
in solution fluxed with other constituents of a volatile nature ab- 
solutely free from paraffine and sulphur, the preparation remain- 
ing in a fluid condition at a temperature above 50 degrees Fahr- 
enheit, and is entirely free from all the objectionable features of 
crude oil. It carries a slight odor, not offensive, which disap- 
pears entirely in a period of two to five days, which is the time 
required for the liquid asphalt to properly set and dry upon the 
surface of the roadway upon which it is applied. It is a scien- 
tifically prepared material, which was developed from several 
years' experiment in treating roads with crude oils for the pur- 
pose of eliminating dust. 

Petrolithic pavement for city streets and country roads is a 
California invention. It consists of natural soil, which to a depth 
of six inches, has been impregnated with crude asphaltic oil, and 
tamped until it is practically as solid as stone, by means of a 
Petrolithic Rolling Tamper. The tamping roller to be used in 
the execution of the work consists of a roller the outer surface 
of which is studded with teeth not less than seven inches long 
and having a surface area of not less than four square inches 
each, the roller itself is of such a weight that the load upon each 
tooth is not to be less than three hundred pounds. 

In April, 1905, the City Engineer of Los Angeles, Cal, gave 
the author the following specifications for surfacing roadways : 

SPECIFICATION. 
Upon the surface prepared and brought to sub-grade shall be spread 
in the following described manner: Two layers of gravel, of the same 
quality as that composing the natural surface of the street, the bottom 
layer to have a thickness of five inches, and the top layer to have a 
thickness of three inches after having been rolled. The first layer, which 
shall contain no stones larger than two and one-half inches in greatest 
diameter, is to be uniformly spread upon the roadway, and well moist- 
ened. The gravel shall be well rammed for at least one foot from the 
gutters, should these be paved, or if the gutters are not paved, then one 
foot from the curb. The remaining portion of the roadway shall then be 
rolled with a roller weighing not less than 250 pounds to the inch width 
of tire. The rolling of the roadway shall commence at the rammed 
portion. All depressions must be promptly filled, moistened and again 
rolled. The rolling must be continued until the surface wil not yield 
under a roller of the weight above described. 



•3 Z 

2 z 




28 



'ASPHALTS' 



SURFACING ROADS. 



ny 



On this surface shall be spread the top layer, which shall be raked 
free from all stones larger than one-half inch in greatest diameter. If 
no gutters are provided, these larger stones shall be raked to the curb 
and distributed over a strip two feet in width next to the curb. If 
gutters are provided then these stones shall be distributed on a strip 
of two feet in width next to the gutter. The top layer of gravel shall 
then be thoroughly compacted by ramming and rolling in the same man- 
ner as specified for the first layer. 

The entire surface between the gutter lines, if there be gutters, or 
between the curb lines if there be no gutters, which shall have been 
rendered perfectly smooth and hard by the process above specified, shall 
then be broken to a depth of not less than two inches by a fine tooth 
harrow, or some similar apparatus, dragged in every direction over it, 
until no part remains untouched. Oil shall then be even distributed over 
the surface in a volume equal to, but not exceeding, the amount the 
surface of the street will absorb in such manner that no oil shall remain 
on the surface. 

After a lapse of not less than twelve hours the surface shall be again 
harrowed, and receive a second application of oil. Any part of the 
street, upon which a portion of the oil or the residue thereof may be 
seen, shall then be sprinkled with sufficient sharp sand to absorb the 
same, and any portions that appear too dry shall receive a further light 
application of oil. 

The entire surface shall then be thoroughly mixed and receive a light 
covering of sand, and be thoroughly rolled and trimmed until no evidence 
of oil remains, except the coloring of the gravel. 

The total amount of oil used shall not be less than three gallons per 
square yard of the street surface. The oil used shall be crude petroleum 
of a density between 11 and 14 degrees gravity Baume, asphaltum base, 
and shall be applied at a temperature not less than 150 degrees Fahr. 



— --: Chapter XVII. 

ASPHALTIC OILS, THEIR CLASSIFICATION AND 
PROPERTIES. 

OILS as a class are fatty organic substances derived from in- 
numerable sources. They may be most conveniently 
divided under three heads, as animal, vegetable, and mineral. 
While oils of the first two classes have been used to some extent 
as dust preventives, mineral oils are by far the most important, 
.and have been most generally used for this purpose. As animal 
and vegetable oils, owing to their lack of heavy binding bases, 
may be ranked as temporary binders, they may be considered most 
conveniently with the lighter mineral oils and emulsions, which 
will be taken up later. 

The value of an oil as a permanent dust preventive lies in 
the quality and quantity of high-binding bituminous base retained 
by the road surface after evaportion of the more volatile con- 
stituents. The bases present in petroleums vary from those of 
almost pure paraffin to almost pure asphalt, many being mixtures 
of the two. While the paraffin oils are of much more value than 
the asphalt from a commercial point of view, the opposite is true 
from the standpoint of their use in dust suppression. An oil 
wholly paraffin is of value only as a temporary binder or dust 
layer. Petroleum is a mixture of a great number of organic bodies 
known as hydrocarbons, together with small quantities of sul- 
phureted, nitrogenized, and oxygenated compounds. The ap- 
proximate composition of crude petroleum is ordinarily deter- 
mined by distillation, but a knowledge of the residuums left after 
distillation is of fare value from the standpoint of dust sup- 
pression. 

There are seven distinct oil fields in the United States, which 
yield oils differing in qualities. The Appalachian, which includes 
the States of New York, Pennsylvania, West Virginia, south- 
eastern Ohio, and parts of Kentucky and Tennessee, produces 
oils which are known as eastern oils or paraffin petroleums, and 



ASPHALTIC OILS. 1 19 

which are therefore of use only as temporary binders in dust sup- 
pression. The Ohio-Indiana field produces oils which are much 
like those of the Appalachian and are also classed as paraffin oils ; 
and the same is true of the Colorado oils. The Wyoming oils vary 
in character from the lighter to the heavy asphaltic oils which are 
found principally in California. The oils from the California field, 
while of the most varied character, consist mainly of more or less 
dense asphaltic hydrocarbons. None of the components are of 
the paraffin series, and, as the percentage of asphatlic residue in 
these oils is usually high and of a good binding character, they 
may be considered the best for use as permanent binders. Oils 
from the Texas field are of a mixed character. All of them con- 
tain some paraffin as well as a greater or less amount of asphaltic 
residue. Some have been used successfully as dust preventives, 
while others are unfit for this purpose. It is needless to say that 
their value lies in the relative amounts of asphaltic and paraffin 
base contained. The Kansas oil field, including Oklahoma, pro- 
duces oils quite similar to those from the Texas field and shows 
a mixed paraffin and asphaltic base. The Louisiana field also 
yields oils similar to the Texas. Some of the wells in the Indiana 
and Kentucky fields have also been successfully used. In gen- 
eral, however, the eastern oils are of the paraffin type and use- 
less as permanent binders; the western oils are of asphaltic 
character and of great value as permanent binders, while the 
southern oils are of 2. mixed character, containing part paraffin 
and part asphalt bases, their value as dust preventives lying in 
the relative amount of asphalt base contained. 

While crude oil has been used to a great extent in the West 
for the purpose of dust prevention, it is often customary in the 
East to partially distill oils containing, asphaltic residues before 
using- them in this connection. By this means many of the more 
valuable constituents are recovered and the residual oils produced 
have a much better binding quality, owing to the fact that they 
contain a larger percentage of asphaltic base. A brief description 
of the principal processes of oil refining and of the properties pos- 
sessed by different types of refined oils will therefore be given. 

Crude petroleum is an only liquid of rather unpleasant odor, 
with a specific gravity ranging from 0.73 to 0.97, according to the 
locality from which it is derived. It varies in color from greenish 
brown to nearly black and often exhibits a reddish brown or 



120 ASPHALTS. [chap. xvii. 

orange color when viewed by transmitted light. It is also some- 
what fluorescent. Sand and water are often mixed with the crude 
oil, but these separate and settle upon standing in the storage 
tanks. In order to recover various products from the crude pet- 
roleum, it is subjected to a process of refining by means of frac- 
tional distillation in a manner somewhat similar to that employed 
for the refining of crude coal tar. 

The most valuable products are the kerosene, or burning oils, 
and a method known as ''cracking," which increases their yield, 
is very generally employed. This is accomplished at a certain 
stage of the distillation by modifying the fire so that only the 
bottom of the still is subjected to a great heat, while the top 
and sides, being exposed to the air, become somewhat cooled. 
By this means the heavy oil vapors are condensed within the 
the still itself, and upon dropping back into the residium, which 
is much hotter than their boiling point, break up into lighter oils 
with lower boiling points with a separation at the same time of 
free carbon or coke, which is deposited in the residium. Here 
we have a condition somewhat similar to that encountered in 
the case of coal tar produced at a high temperature. As the free 
carbon is not a binder, it is useless in a dust preventive, and 
when present in large amounts is apt to produce the same bad 
effects in an oil as in a tar. 

The residium of the various petroleums have been used to 
a great extent as fluxes for softening the solid native bitumens used 
in the paving industries. Their various characteristics and prop- 
reties have therefore been given considerable study. As the 
character of the residues present in both the crude and refined 
petroleums is of the greatest importance from the standpoint 
of dust suppression, the results obtained from a study of these 
fluxes should be of service in determining the suitability of vari- 
ous oils for this purpose. The character of the residue will nat- 
urally vary as the crude petroleums vary, although, as has been 
shown, the method of preparation may produce considerable 
effect upon the residue. 

The paraffin petroleum residuums are of a soft, greasy char- 
acter and, as their name implies, contain a large amount of par- 
affin hydrocarbons and paraffin scale or crude paraffin. A road 
surface treated with material of this character will be dustless 
for the time being, but in damp, rainy weather will become cov- 




29 



"ASPHALTS' 



ASPHALT1C OILS. 12 1 

ered with a slimy, greasy mud, which is easily washed away and 
leaves the road is as bad, if not worse, condition than it was 
before treatment. When the crude or even the residual oil is 
used solely as a binder, it may therefore be predicted that the 
outcome will prove a failure. 

The base held by the California petroleums is composed of 
bitumens resembling asphalt. The residium contains no paraffin 
and, if cracking has not been employed in its preparation, carries 
but little free carbon. The specifications for California fluxes 
call for not over 6 per cent, fixed carbon. Both the crude oil 
and the residiums, if properly prepared, act as excellent binders 
and have, as a rule, given the best results of any oils which have 
been used as dust preventives. 

The semi-asphaltic oils, such as those obtained from Texas, 
carry an aphaltic base, but also a considerable amount of paraffin 
hydrocarbons and a little over I per cent, of paraffin scale. While 
somewhat inferior to the California products, good results have 
often been obtained from their use on roads in both the crude 
and the refined state. Those which contain the greatest amount 
of heavy binding bitumens and the least amount of paraffin scale 
are, of course, to be preferred. In order to obtain the best re- 
sults the residiuums, as well as the crude oils of asphaltic or 
semi-asphaltic character, should be comparatively free from water. 

Sometimes the residues from the distillation of petroleum, 
while yet hot, are subjected to the action of a jet of air, which 
has a tendency to thicken or harden them. It is doubtful, how- 
ever, if an oil thus treated will be improved for use as a dust 
preventive, as the life of the oil is apt to be destroyed and its 
lasting qualities as a binder lessened. 

The use of a paraffin petroleum is to be avoided, as a good 
crude product is to be preferred to a badly cracked residiuum 
or one produced from a poor quality of crude petroleum. Con- 
siderable attention has been paid to the actual quality of oils 
which have been employed as dust preventives. A number of 
specially prepared or refined oil products are now on the market 
for use on roads, both in the form of residiuums and emulsions. 
The residuum products have been prepared from asphaltic or 
semi-asphaltic oils by methods similar to those described, while 
the emulsions are usually residuums which have been treated with 
saponifying agents in order to make them miscible with water. 



122 ASPHALTS. [chap. xvii. 

Owing to the fact that oils from a number of wells are com- 
monly run through the same pipe lines from the wells to the 
storage tanks, it is often difficult to obtain two lots of oil having 
exactly the same properties, even when purchased from the same 
source. It is very important, therefore, that an examination of 
each lot of oil be made before attempting to use it for the pur- 
pose of dust prevention. Sometimes a partial chemical analysis 
is necessary, but in the majority of cases a few simple tests will 
determine its suitability for this purpose. These methods of ex- 
amination are described later. It is also a wise measure to ex- 
amine residuums even when they are especially advertised as 
road preparations, for, as has been stated, there is a strong 
tendency among refiners to crack their oils in order to increase 
the yield of illuminants, and when this is done the value of the 
residiuum for the purpose of dust prevention will be considerably 
lessened. If the road engineer understands thoroughly the prop- 
eties possessed by the oil which he is handling, he will be able 
to avoid many dismal failures which might otherwise occur. 

Some of the results obtained from an examination of vari- 
ous crude and refined petroleums in the New York Testing La- 
boratory are given in the following tables in order to show the 
differences in properties possessed by the different kinds of ma- 
terial. They do not in any sense represent absolute values for 
the different classes of oils, but will serve to give a general idea 
of the relative characteristics of each. 

Table IX. 
RESULTS OF TESTS OF CRUDE PETROLEUMS. 

Volatil- Volatil- Volatil- 

Flash- ity at ity at ity at 
Specific ing 110° C, 160° C, 205° C, 

Kind of oil. gravity, point. 7 hrs. 7 hrs. 7 hrs. Residue. 

°C. % % % % 

Pennsylvania, paraffin 0.801 (a) 47.3 58.0 68.0 b32.0 

Texas, semi-asphaltic 904 43 20.0 27.0 49.0 c51.0 

California, asphaltic 939 26 d42.7 e57.3 

aOrdinary temperature. cQuick flow. 

bSoft. dVolatility at 200°, 7 hrs. 

eSoft maltha; sticky. 

It will be noticed from the foregoing results that in the 
samples examined the specific gravity increases from the paraffin 
to the asphaltic oil. This is also true of the percentage of resi- 
due, while the volatility decreases correspondingly. The residues 



ASPHALTIC OILS. 123 

range in character from soft and probably greasy through an 
intermediate and but slightly viscous stage to the more or less 
liquid maltha of good adhesive properties. A rough idea of the 
character of these bases may be formed by rubbing a little of 
the residue or even of the crude oil between the finger and thumb. 
Those of a paraffin nature will feel greasy, while those of an 
asphaltic character will often exhibit an adhesiveness which is 
easily distinguishable. The color and odor will also indicate the 
character of the crude material to those familiar with the different 
varieties. In comparing the Pennsylvania with the Texas oil, 
it will be seen that the former carries a higher per cent, of light 
oils than the latter. A comparison of the residuums obtained 
from refining oils similar to those described in the above table 
is shown in the following table: 

Table, X. 

RESULTS OF TESTS OF PETROLEUM RESIDUUMS. 





Volatil- 










Flash- ity at 










Specific ing 200° C, 




Solid 


Fixed 


Kind of oil. 


gravity, point. 7 hrs. 


Residue. 


paraffin. 


carbon, 




°C. % 


% 


% 


% 


Pennsylvania, paraffin . . . 


,. .. 0.920 186 14.2 


a85.8 


11.0 


3.0 


Texas, semi-asphaltic 


974 214 6.2 


a93.8 


1.7 


3.5 


California, asphaltic 


1.006 191 17.3 


a82.7 


0.0 


6.0 



aSoft. 

In comparing these results an increase in specific gravities 
in the same direction as in the case of the crude petroleums will 
be noticed. The volatility and percentage of residue, however, 
are not in the same order. As these are dependent entirely upon 
the point at which distillation is stopped in the process of re- 
fining, such a result is to be expected. The percentage of solid 
paraffins is found to decrease to zero as the character of the oil 
becomes asphaltic. Only 11 per cent, was found in this particular 
sample from Pennsylvania, but it is not uncommon for oils of 
this nature to carry as high as 33 per cent, paraffin. The amount 
of fixed carbon is found to increase with the asphaltic character 
of the oil, and this fact is quite general, owing to the greater 
tendency of the asphaltic oils to crack during distillation. 

In comparing the crude oils with the residuums, it will be 
seen that the latter, as would naturally be supposed, carry a 
greater percentage of residue, and, other things being equal, are 



124 ASPHALTS. [chap. xvii. 

therefore of more value as permanent binders. A considerable 
difference is also seen to exist between their flash points, which 
is the temperature at which their most volatile products flash 
when brought in contact with a flame. As a general rule, it is 
not difficult to distinguish between a crude and a residual oil, 
but in cases where any doubt may exist the flash point is a fairly 
accurate indicator. Thus, in the case of the crude Texas oil and 
the Pennsylvania residuum, we find that their specific gravities 
are quite close together, and some doubt might exist as to which 
was crude and which residual. A determination of their flash 
points would at once settle this question. 




30 



'ASPHALTS' 



Chapter XVIII. 
APPLICATION OF ASPHALTIC OILS. 

MANY valuable facts have been learned in regard to the 
application of oils to road surfaces, although, owing to 
contradictory results, considerable differences in opinion seem 
to exist as to the actual and relative values of different kinds of 
oils under the same conditions and under varying conditions. 
This is, to a great extent, due to lack of knowledge in regard to 
the properties of the material used and to the fact that climatic 
conditions and the character of the road treated have a much 
more important bearing upon the results than is usually realized. 

The subject of oil application has received considerably more 
study in our country than has been given it by European nations. 
It is true that various experiments have been carried on in Eng- 
land and France with a number of different oils, but owing to 
the lack of a proper base in these oils the results have been dis- 
couraging. Shale oils and Russian petroleum residuums, known 
as "masut" or "astatki," have been employed, as well as certain 
vegetable oils, such as oil of aloes. They have all been found 
effective as temporary dust preventives, but in rainy weather 
produce a greasy, disagreeable mud and soon disappear from the 
road surface. The best results have so far been obtained with 
heavy oils applied in the form of a spray while hot. 

As the application of the temporary binders or lighter oils 
can best be considered in connection with that of oil emulsions, 
the application of the heavier oils only will be taken up here. 
Crude petroleum, as well as residuums and specially prepared 
oils, have been used with more or less success on earth and 
gravel roads, as well as on stone roads. 

APPLICATION TO MACADAM SURFACES. 

In applying oil to a macadam surface, holes and inequalities 
should be repaired ; it has not been found necessary to remove all 



126 ASPHALTS. [chap, xviii. 

dust from the road surface, but sticks, leaves and other detritus 
fo an organic nature should be removed. 

The crude or refined oil may be applied either cold or hot, 
according to its viscosity and ability to penetrate the road sur- 
face. The application of cold oil is considerably the cheaper and 
is to be preferred on that account. Most crude oils and some of 
the lighter residuums have been used in this way with good results, 
but it has been found necessary to heat the heavier products be- 
fore application. 

If much work of this kind is to be carried on in one locality, 
it is sometimes the custom to erect a stationary heating plant at 
a convenient railroad siding. A plant of this sort has been de- 
scribed in a previous publication,* and consists of a receiving tank 
of one tank-car capacity placed preferably so that the oil may be 
run in by gravity from the car. A heating tank set at an elevation 
sufficient to allow the hot oil to run into the distribuing wagons 
and fitted with steam coils through which superheated steam may 
be forced is placed near the receiving tank. The oil may be 
pumped into this heating tank as required and heated to any de- 
sired temperature. Very often the heating is carried on in the 
tank car, and the hot oil run directly into the distributing wagon. 
When sufficiently fluid, it can then be applied to the road by means 
of a large pipe and broomed into the surface in the same manner 
as tar. Patented distributing devices have been employed which 
can be attached to almost any form of tank wagon and which, if 
the oil is fluid enough, will do away with the necessity of broom- 
ing. An oil applied by this means will, however, have to be heated 
to a higher temperature than in the former case, as the openings 
in the distributer are of small dimensions and will not allow the 
oil to pass freely if it is in a very viscous state. 

The main object is to obtain an even coating, which shall be 
well absorbed by the road surface. The application of a large 
excess of oil should be avoided, as it is sure to make the surafce 
sticky and disagreeable. A covering of sharp sand or one-half- 
inch stone screenings should be applied after the oil has been al- 
lowed to penetrate as much as possible, in order to take up all 
excess, and the surface thus formed should be rolled until well 
compacted, additional sand or screenings being thrown on where- 



*Use of Mineral Oil in Road Improvement, Yearbook Dept. Agric, 1902 p 
446. - 



APPLICATION OF ASPHALT1C OILS. 127 

ever the oil shows a tendency to force its way to the surface and 
produce a sticky condition. Sometimes two or three courses of 
oil and screenings are applied. It is usually considered better to 
allow the freshly oiled road to dry out to some extent before 
applying the top dressing, but in cases where it is impossible to 
keep traffic away the same methods may be employed as in the 
case of tar, i. e., either one-half the width of the road may be 
treated at one time or the sand or screenings may be applied at 
once. If the oil is well absorbed it is not always necessary to em- 
ploye the roller, as ordinary traffic will consolidate the surface in 
the course of time. 

APPLICATION DURING CONSTRUCTION OF MACADAM 

' ROAD. 

The application of oil during process of construction has been 
carried on with the greatest success in California, where the heav- 
iest asphaltic oils are found. The residuums obtained from the 
partial distillation of these oils have so far given the best results 
when properly applied. The treatment is essentially the same as 
with tar, the object being to build a road containing a low percent- 
age of voids, so that the oil will act as a binder only and the strain 
of traffic be borne by the road stone. Considerable attention should 
be paid to proper drainage of the road, as it is essential that the 
foundation be perfectly dry. The macadam is built in the usual 
manner and each course thoroughly rolled until the whole road 
is well consolidated. If water is used during the process of con- 
struction sufficient time should be given for the road to become 
perfectly dry before applying the oil. The hot oil is applied by 
means of a tank wagon fitted with a distributing device which 
insures an even distribution. Any excess of oil is taken up by the 
application of a sufficient covering of sand and screenings, and 
the road is then opened to traffic. 

A road constructed in this manner will usually require from 
% to iy 2 gallons of oil per square yard, depending upon the qual- 
ity of oil employed and kind of road surface treated. 

The softer and more porous rocks, such as limestone, permit 
of a better penetration than the harder rocks, such as trap and 
granite, but good results have been obtained by the use of both 
kinds. Oils as a class seem to penetrate better than tars, as they 
do not harden as quiclky upon exposure to the air. In order to 



128 ASPHALTS. [CHAP. XVIII. 

keep the road in proper condition, repairs should be made as often 
as necessary, and in the same manner as in the case of tars. By 
this means rapid disintegration will be prevented, which would 
otherwise occur if water were allowed to accumulate in the worn 
places. 

APPLICATION TO GRAVEL ROADS. 

A gravel road is oiled in much the same way whether it is an 
old road or one under construction, as only the upper course is 
treated in either case. It is especialy important in a road of this 
kind that the drainage be good, and this matter should be attended 
to first of all. Any holes or pockets which may exist should be 
cleared out, if much fine material is present, and filled with clean, 
fresh gravel, so that the surface of the -road will be uniform when 
the patches have been sprinkled and rolled. If the lateral drain- 
age is bad, the entire surface should be loosened and brought to 
proper grade and crown by the addition of new material before 
the oil is applied. In this case more oil will be required to effect 
a good bond than if the old-compacted surface w T as treated, but the 
results will be of a more lasting character. The oil may be applied 
either cold or hot, according to its viscosity, by any of the methods 
already described. It should contain a high percentage of good 
asphaltic base, or otherwise the material near the surface will be- 
come loose, owing to the lubricating qualities of the oil. The use 
of too much oil should be especially avoided, and all excess should 
be taken up by the addition of fresh gravel. Where the surface 
treated is loose and contains a considerable amount of clay, the oil 
may be worked into the upper course by raking, which insures an 
equal distribution. After application of the oil, the road should be 
rolled until properly compacted, and as this is apt to bring some 
of the oil to the surface, fresh material should be added where 
necessary. If the freshly oiled road is not well rolled, the action 
of traffic will bring the oil upward ; a soft spongy surface condition 
will be produced; loose, oily particles will be thrown out by rap- 
idly moving vehicles; and the oil will be tracked by pedestrians. 

Oil is applied to a gravel road during construction in a man- 
ner quite similar to that already described, but certain points in 
regard to the method of construction should be noted. These facts 
are well presented by the Commissioner of the Department of 
Highways of California* in a report which contains specifications 



'Biennial report, 1906. 




WILLETT'S ROAD (OILED), LONG ISLAND, N. Y. 
Oiled with Gulf Refining Company (Asphaltum) Road Oil. 



31 



"ASPHALTS' 



APPLICATION OF ASPHALTIC OILS. 



129 



used in certain parts of that State for the construction of oiled 
graveled streets. As California has been most successful in this 
kind of work, a study of the methods used there should be of great 
value to experimenters in other localities. Certain portions of 
these specifications in condensed form are given below for the 
purpose of emphasizing the most essential points. 

Before placing the gravel the subsurface must be brought to 
grade and rolled. Upon this subsurface two layers fo good gravel 
should be applied, the bottom layer having a thickness of 5 inches 
and the top a thickness of 3 inches after being rolled. The first 
layer should contain no stones larger than 2y 2 inches in greatest 
diameter. The gravel must be uniformly spread on the roadway 
and well moistened, rammed 1 foot from the gutter or curb, and 
the remaining portion rolled with a roller of the type before 
specified. All depressions must be promptly filled, moistened, and 
again rolled, the rolling being continued until the surface will not 
yield under the roller. On this surface the top layer of gravel, free 
from all stones larger than 1 inch in greatest diameter, should be 
applied and compacted in the same manner as the first layer. Oil 
should then be evenly distributed over the entire surface at the 
rate of one-half gallon per square yard, and covered with clean, 
sharp sand until no oil can be seen. After the lapse of not less 
than twelve hours, another application of oil should be made and 
sand distributed in the same manner and the whole surface rolled 
until unyielding to the roller, as before described. 

These specifications require that the oil be crude and that it 
be applied at a temperature not less than 150 F. nor above 190 
F. Certain methods of testing the properties of the oil are included 
in the specifications, and a consideration of these tests will be 
found later. In regard to measuring the petroleum, however, it 
may be said that the volume at 6o° F. is taken as normal, and a 
deduction of 0.1 per cent, is made for every io° increase over this 
normal temperature as a correction for expansion by heat. 

USE OF OIL ON EARTH ROADS. 

The use of oil on earth roads was first tried in this country 
in California. Crude petroleum was sprinkled upon the road for 



130 ASPHALTS. [chap, xviii. 

the purpose of laying the dust only. It proved to be a very 
effective dust layer, and in some cases improved the condition of 
the road surface to such an extent that popular attention was 
aroused, and as a result many experiments were made with a view 
not only to laying the dust, but to hardening the surface. Since 
then oil has been used with varying success and failure, and much 
valuable information has been derived from the experiments. Cali- 
fornia is particularly favored for work of this nature, owing to its 
climate and the character of its roads, as well as to the excellent 
road-building properties of its oils. Although it is impossible to 
duplicate these conditions in other localities, the lessons learned 
from the numerous experiments conducted in this State are of 
great interest as offering suggestions for work of a similar nature 
in other places. 

It has been found that the character of the soil plays a most 
portant part in the results obtained, and different kinds of soils 
have to be treated in different ways. Alkali soils disintegrate the 
oil and destroy its binding qualities. A sandy loam is the most 
suitable for treatment, and almost invariably gives good results 
when treated in the proper manner with an oil of good binding 
quality. From a physical standpoint clay is probably the worst 
of all, as it does not absorb the oil well and exhibits a tendency to 
ball up and give trouble. Sand should therefore be added to the 
clayey surface until this difficulty is overcome. As in the case of 
gravel roads, special attention should be paid to drainage, and the 
roadbed should be dry when the oil is applied. If the foundation 
is water-soaked, it soon loses its ability to support the surface 
properly, which will then break through in weak spots. 

The use of too much oil should be avoided, as it will produce 
a spongy surface condition and increase the draft of vehicles to a 
considerable extent. It is most important to keep a road thus 
treated in good repair. Whenever a rut or hole develops it should 
be cut out, oil should be poured in, and it should be filled up with 
good earth or sand. The loose material should then be thoroughly 
tamped until even with the surrunding surface. 

Besides the method of oiling earth roads already described, 
another has recently been employed with considerable success in 
California. This mthod differs from the other in two essential 
particulars. The first of these is that water is applied during the 
process of oiling, and the second that consolidation is produced by 



APPLICATIOX 0J ; ASPHALTIC OILS. 13! 

a special tamping device. The method has given satisfactory re- 
sults with sand and clay roads, as well as with loam and gravel, 
and is conducted as follows : 

The road is first plowed up to the depth of 6 inches and prop- 
erly crowned. All clods and lumps are then thoroughly broken 
up by means of a harrow, and the roadway is well sprinkled with 
water. A specially constructed rolling tamper is then used by 
which the lower portion of the loose earth is compacted to a depth 
of about 2 inches, except in cases where the subgrade is unusually 
firm. 

After the lower portion is made firm by this means a heavy 
asphaltic oil is applied at the rate of about iy 2 gallons per square 
yard, and a cultivator is passed over the road until the oil and 
earth are thoroughly mixed. The tamper is then used again, and 
the road is further compactd until only \)/ 2 inches of loose mateiial 
remain on top. This is lightly harrowed and sufficient water is 
added to moisten it. Oil is again applied, and the surface is rolled 
with the tamper until firm, and finally it is ironed down with an 
ordinary roller additional applications of earth bein made wher- 
ever necessary to take up any excess of oil. 

A road constructed in this manner will require from 2.y 2 to 3 
gallons of oil per square yard. It is hard and dustless and resem- 
bles asphalt. 

The California oils are best adapted for this method of road 
building, but the cost of transportation to the Eastern States at 
the present time raises the price to a prohibitive figure. The 
Texas and some of the Kentucky oils are the best available for 
these localities, and range in price from about 4 to 8 cents per 
gallon, according to locality. The residuums and special prepara- 
tions vary from 2 to 12 cents per gallon. It is impossible to esti- 
mate cost of application except for individual cases. 

All kinds of properly oiled roads are dustless, noiseless, water- 
proof, and resilient, and offer but little resistance to traffic. The 
crude oils have a rather unpleasant odor, which soon passes away. 
Both the crude and residual oils exhibit a somewhat weak germi- 
cidal action. If an excess of oil is present upon the road surface, 
an oiled mud is formed in wet weather which is damaging to 
clothes and the paint on vehicles, but this condition is not met with 
if the proper amount of the right kind of oil is employed. 



132 ASPHALTS. [chap, xviii. 

WATER AND SALT SOLUTIONS. 

The temporary binders as previously defined are materials 
which have to be applied at more or less frequent intervals in order 
to suppress dust. Their primary object is to lay the dust only, 
although they may also tend to preserve the road from wear. No 
distinct line can be drawn between the permanent and temporary 
binders, but in general the latter class may be said to embrace 
water, salt solutions, the lighter oils and tars, and various emul- 
sions. 



SPECIFICATIONS FOR MINERAL OILS TO BE USED AS 
DUST PREVENTIVES OR ROAD PRESERVATIVES. 

As oils may be used on almost any kind of road either as 
temporary or permanent binders, their requisite qualities will de- 
pend upon the use to which they will be put. Almost any asphaltic 
or semi-asphaltic oil will prove satisfactory as a temporary binder 
if properly applied either in the form of an emulsion or in its 
natural state. Specifications for the properties of permanent bind* 
vers only will therefore be considered. 

According to Ellery a good road oil should contain at least 
40 per cent, of commercial "D" grade asphalt, having a penetra- 
tion of 6o° and no more than 3 per cent, of foreign matter and 
water. When employed in the construction of oiled graveled 
streets at Los Angeles, Cal., the following specifications* were 
adopted for crude oil: 

The specific gravity shall not be lower than io° (1.000) nor 
higher than n° Baume (0.993). 

All crude petroleum shall contain not less than 70 per cent. 
"D" grade asphalt, California standard. 

All crude petroleum shall be tested for water and sediment. 
Deductions for water and sediment in crude petroleum will be 
made in exact proportion to the percentage of such water and 
sediment found. 

In the construction of asphaltic oiled and tamper-rolled dirt 
roads at Santa Monica, Cal., the following characteristics were 
specified : 



*Biennial Report of the Dept. of Highways of California, 1906, p. 44. 





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.32 



'ASPHALTS' 



APPLICATION OF ASPHALTIC OILS. 



*33 



The oil shall be from 12 to 14 Baume (0.986-0.972) test 
at a temperature of 6o° F. and contain not less than 70 per cent, 
of pure liquid asphaltum, natural non-processed oil to be subject to 
gasoline test for water and foreign matter, and not to contain over 
2 er cent, of water or foreign matter. 

From experiments conducted by the Office of Public Roads 
it would seem that only reduced or residual oils are apt to prove 
satisfactory as permanent binders if they are semi-asphaltic in char- 
acter. The following specifications are therefore suggested for 
this class of oils : 

1. The oil shall have a specific gravity of not less than 0.95. 

2. Its flash point shall be not lower than 300 F. 

3. It shall be free from water as determined by the gasoline 
test. 

4. When heated to 400 F. in the manner previously described 
for seven hours its loss in weight should not be over 35 per cent. 
The character of the residue should be smooth and nearly solid 
when cold, but not so hard that it may not be easily dented with 
the finger, and when soft it should pull to a long, thin thread. 

5. The oil shall be soluble in carbon disulphide to the extent 
of 98 per cent., and in 88° naphtha to at least 88 per cent. 

The methods of examination and specifications for asphalt and 
other solid materials have not been considered in this chapter for 
obvious reasons. They belong to works on the subject of pave- 
ments. In conclusion it may be said while specifications for dust 
preventives and road preservatives should prove of great service 
in most cases in securing proper materials they are of no value 
unless the proper method of applying the material to the road is 
employed. So far as possible these methods have been outlined, 
but local conditions will often necessitate modifications, and much 
will therefore depend upon the experimenter or overseer of the 
work. 



Chapter XIX. 
SPRINKLING WITH ASPHALTIC OILS. 

THE Standard Oil Company is now putting out an asphalt 
oil under the brand of ''Standard Asphalt Road Oil," it is 
a dust layer and at the same time a surface binder. The customary 
plan is for the municipalities to purchase the oil in tank cars, and 
either sprinkle it with their own labor or have some local contrac- 
tor do the work, using an ordinary watering cart. From one- 
third to one-half gallon of oil per square yard of surface will pro- 
duce good results, the quantity used depending upon the nature 
and condition of the road. 

The New York State Engineering Department has used large 
quantities of "Standard Asphalt Road Oil," treating State roads 
at Port Jervis, Mt. Upton, Schuylerville and other points. County 
roads have been oiled at Yonkers, Rye, Port Chester, Pleasantville, 
White Plains and Hartsdale, New York. Norwalk, Darien, Fair- 
field and Greenwich, Connecticut, and numerous other towns, and 
the results have been more than gratifying. 

In many cases the cost of oiling is less than water sprinkling, 
from the fact that it is only necessary to oil once a season, whereas 
water sprinkling is a daily affair. 

The Standard Oil Company also have an asphalt binder, 
known as "Standard Macadam Asphalt Binder," this is a heavy 
limped asphalt used in the construction of roads where asphaltic 
material is used. Roads of this character are sure to come in the 
East, California having demonstrated their durability and supe- 
riority over the ordinary macadam road. At Rye, N. Y., 6^4 miles 
of road are being built using the Asphalt Binder in its construction. 

The Standard Oil Company, realizing the constantly increas- 
ing demand for asphalt oil for surfacing roads has created a dis- 
tinct department for supplying the same, not only to municipalities 
but to private individuals under the management of Air. Henry 
Fisher. 



SPRINKLING WITH ASPHALTIC OILS. 135 

In this connection the report of W. H. Dunn, Superintendent 
of Parks to the Board of Park Commissioners, Kansas City, Mo., 
April 20, 1908, on "Oiling Roads," is interesting. He stated that 
undoubtedly the most important item of road maintenance for the 
past fiscal year has been the remarkably good results obtained from 
oiling. 

Continuing the experiment with oil on rock roads, begun in 
the summer of 1906, the entire system of driveways was, in 1907, 
treated with residuum oil, now commonly called road oil. He 
continued : 

"I attribute our success, in a large measure, to the fact that 
we had well-built macadam roads to begin with, demonstrating 
that, when to a perfectly built macadam road with a solid foun- 
dation and hard, smooth surface, is added the road oil for a dust 
preventive and protection to wearing surface, an inexpensive treat- 
ment is given that proves remarkable in its results. 

"Our roads to-day, after one year's trial, are in excellent con- 
dition, have gone through the winter with less breaking up from 
freezing and thawing than usual, and without a particle of dust 
after having been once oiled, and without attention beyond the 
ordinary sweeping. 

"Aside from its value as a dust preventive, the oiled road shows 
this interesting item of reduction in maintenance expense: 

"Sprinkling driveways with water, for the fiscal year ending 
April 15, 1907, cost $14,011.32, or an average of 2.4 cents per 
square yard. The area of pavement to have been sprinkled in 
1907 (had not oil been applied) would have cost $16,207.32. 

"The total cost of oiling for the year was $10,671.44, a direct 
saving in the one item of sprinkling of $5,538.88, or 34 per cent. 

"I believe with an occasional light application of oil through 
this season we will still improve the wearing surface of our roads, 
and eventually obtain an ideal dustless pleasure drive. 

"The damage to wearing surface comes largely from attrition 
of the grit or dust on the roadway. Oil compacts this grit or dust, 
and immediately checks deterioration from this source, preventing 
any damaging effect from automobile travel. 

"The road oil available for Kansas City is a paraffine base oil, 
and becomes somewhat slippery when applied on steep grades, but 
is not noticeable on moderate grades. To overcome this objec- 
tion, a mixture of commercial asphalt with residuum oil has been 



136 ASPHALTS. [chap. XIX. 

tried on The Paseo from Howard to Twenty- fourth Streets, with 
excellent results, and further experiments will be made this year 
with this material and with an asphaltic oil from the Kentucky 
field; with this character of oil, on grades exceeding 4 per cent, 
I feel sure we will have largely solved the dust problem in a 
manner satisfactory to all concerned. 

"I submit the following statement of oiling operations for 1907, 
somewhat in detail, covering the oiling operations for the past 
season with a plan of the unloading tanks and method of applica- 
tion. 

"Two steel receiving tanks of 8,000 gallons capacity each 
were erected near our spur track on the Belt Railway, as illus- 
trated. The railroad tracks at this point are at sufficient eleva- 
tion to permit unloading tank cars by gravity, the receiving tanks 
also being at such height as to allow the sprinkling wagons to load 
by gravity. A four-inch pipe line connects the receiving tanks to 
a short upright pipe in the center of switch track, which is con- 
nected to the outlet in bottom of tank car by a short piece of 
adjustable six-inch hose, fastened with iron clamps around outside 
of pipes. 

"A portable four-horse power boiler is erected, with ^-inch 
steam pipe running to each tank, which provides ample steam to 
heat the oil so it will run freely and remain warm until delivered 
on the street. 

"This plant for unloading has worked very efficiently and cost, 
erected and all connected up, approximately $750.00. 

"It was found to be not essential to heat the oil handled in hot 
weather, after the middle of June, and until the middle of Sep- 
tember the oil ran freely, and no particular object was gained by 
heating. 

"Adapting the ordinary street sprinkling cart for distributing 
oil on the street was a very simple matter, consisting of simply 
attaching a tin trough six inches in width, six inches in depth, 
and long enough to enclose the discharge valves, perforated with 
% -inch holes about one and one-half inches apart. The oil allowed 
to come into this trough through the valves is then evenly dis- 
tributed over the road. 

"Applying oil to the roadway by any process is dirty work 
and will inconvenience the public for a short time while the road 
is being treated. To avoid accidents, barricade the section to be 




33 



'ASPHALTS' 



SPRINKLING WITH ASPHALTIC OILS. 137 

treated (using one side of the street at a time), place a sign, "fresh 
oil," on the barricade, which gives the public fair notice, and then 
go ahead. 

"The best results were obtained when the road was absolutely 
dry and hot. 

"After sweeping the road as clean as possible with a rotary 
street broom, leaving the sweepings along the edge of the gutter 
to prevent the oil running on the cement work, the oil was applied 
over the entire surface and thoroughly spread with brooms, after 
which the sweepings from the gutter, with sufficient limestone 
screenings to form a light dressing, were cast over the oiled sur- 
face and rolled down with a road roller. The object in using the 
screenings is to absorb such oil as does not penetrate into the road, 
and as soon as screenings are applied the work is finished, and 
no further inconvenience to the public is encountered. 

Table XL 
COST OF OILING. 
"The first application made during May and June, 1907, cost 
as follows : 

Square yards of pavement oiled. 3754J5 

Gallons of oil used 120,477 

Total cost on road $5>559-83 

Average gallons per square yard 0.32 gal. 

Average cost per square yard 1 48-100 cents 

SECOND APPLICATION. 

Square yards pavement oiled. 635,145 

Gallons oil used 156,888 

Total cost on road $5,111.61 

Average gallons per square yard 0.247 

Average cost per square yard $0.00805 

TOTAL OPERATIONS FOR THE YEAR. 

Two applications on 375,415 square yards cost $8,581.92 

One application on 259,730 square yards cost 2,089.52 

Total cost for the year $10,671.44 

Total number of square yards oiled (two appli- 
cations on most of it) 635,145 

Equivalent to one application on 1.010,560 sq. yds. 

At an average cost per square yard for oiling of $0.01055 



138 ASPHALTS. [chap. xix. 

The quality of oil used was a residuum of 20 to 21 gravity, 
Baume. 

Total amount of oil used, 33 cars, or 277,365 gallons. 

Average amount of oil per square yard, 0.274 gallon. 

Average price paid for oil on track, $0.0184 per gallon or 
77^2 cents per barrel of 42 gallons. 

"The above record covers all cost of labor, supplies and oil, 
but does not include the cost of the unloading plant." 



Chapter XX. 

LATEST VIEWS OF CONGRESS ON ASPHALT 
SURFACING. 

AT the Good Roads Convention, held at Atlantic City, Sep- 
tember 25 and 26, 1908, Mr. James E. Owen, M. Am. Soc. 
C. E., of Montclair, N. J., in speaking on "What a New Jersey 
Engineer Should Do," said : 

"First, we must abandon the idea that it is necessary to have 
hard roads; secondly, they must be elastic by the interjection of 
a suitable material; and, thirdly, they must wear but little. The 
experiments with tar show that a softer stone is better than a hard 
one. Slag, limestone, granite or trap will be the order of prefer- 
ence. Appreciating this, the careful insistence of selected material, 
such as trap or granite, which has been our previous practice, need 
not be made, and the natural local stone or gravel can be made 
available. 

"It seems hard for me, as an engineer who has been giving 
his lifework to the construction of these so-called hard roads, to 
take everything back; but with the trend of times and the growth 
of knowledge, I am convinced that the old practices will pass 
away and a new era of road construction will come to the fore. 
This idea dawned on me some years ago, and it is now a convic- 
tion. 

"Now another and final point — that is maintenance. With an 
elastic medium in the natural material the wear is almost elimi- 
nated; there is no grinding of the surface, no dust and, conse- 
quently, no loss. This may seem rather visionary, but two instances 
in my own knowledge confirm the statement. About eight years 
ago an asphalt pavement was substituted for a Telford. The travel 
was so great that four to six inches of stone was ground up in 
two years. Since the reconstruction, no repairs have been made, 
and the pavement is in exactly the same perfect condition to-day 
as when laid. Asphalt, be it understood, is an elastic medium." 



I 4 ASPHALTS. [chap. xx. 

He referred to the very exhaustive experiments made in Rhode 
Island by Mr. Arthur H. Blanchard, Assoc. M. Am. Soc. C. E., and 
quoted from his remarks as follows :* 

"The conclusions arrived at are these: 'First, that highways 
subjected to heavy, high-speed motor-car traffic should be built 
with a bituminous macadam surface, constructed by the mixing 
method; second, that existing macadam roads subjected to a similar 
traffic should be reconstructed as bituminous macadam roads, using 
the penetration method, or, if resurfacing with new road metal is 
required, by using the mixing method ; and, third, that the economi- 
cal and efficient treatment of macadam roads subjected to a mode- 
rate amount of motor-car traffic is at present a matter of con- 
jecture, requiring for elucidation the acquisition of reliable detailed 
information with reference to the use of the various palliatives 
now on the market.' " 

Among the materials upsed under his supervision was a Texas 
asphalt. It was purchased from the Texas Company, and cost, 
delivered at South Ferry, $21.50 per ton of 250 gallons. The cost 
of the haul from the station to the road, an average distance of 
2,000 feet, was $0.10 per barrel of 42 gallons. Therefore the cost 
of the asphalt on the road was $0.09 per gallon. This asphaltic 
product is listed by the Texas Company as Texas Asphalt, Grade 
H. Analyses yields practically no volatile matter to 260 Fahr. ; 
a melting point of 140 Fahr., and only 8.8 gr. per gallons in a 
water solution. 

Mr. George C. Diehl, County Engineer of Buffalo, N. Y., said 
that asphalt in some form will be the future State road material 
of the country. Mr. Diehl declared that asphalt, mixed well with 
stone and other materials, made a durable and elastic road. The 
author, speaking extemporaneously, said in part : Good roads meant 
in these days of the automobile, dustless roads, and that at the 
forthcoming International Congress on Good Roads, to be held 
in Paris, the vital question in the convention would be the most 
approved method of surfacing the roads of the world. To his 
mind there was no uncertainty as to the fact that asphalt in some 
of its various forms would be the matrix of surface mixtures; 
the top of the road must be waterproof, in other words — "dustless" 
— and that object could alone be attttined by the use of asphalt. 

*From a paper read before the American Society of Civil Engineers at Den- 
ver, Colo., June 25, 1908. 



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34 



'AS PH ALTS' 



ASPHALT SURFACING. 141 

He said that for over thirty years he had made the subject of 
good city streets his study, and that during the administration of 
the late General Newton, previously Chief of the Engineer Corps 
of the United States Army, he had been called on to act as special 
inspector of asphalt pavements, subsequently acting as general 
inspector of pavements of the City of New York, and so super- 
vised, under the direction of the late D. Lowber Smith, C. E. 
(Ponts et Chausses, Paris), the varied street pavements then in 
vogue. These naturally included the Telford-Macadam pavements 
which at that time — 1886, 1887 — proved the best pavement for the 
boulevards in the upper part of the city. To-day these pavements, 
with an adequate surfacing of two to three inches of asphalt con- 
crete, would afford a durable resiliant waterproof and dustless 
roadway. As he was not speaking in the interest of any company 
or asphalt industry, he called attention to the fact that municipal 
officials could purchase the materials and apply the same them- 
selves. He said that the methods of utilizing asphalt with other 
materials in the most satisfactory manner could not yet be con- 
sidered as definitely settled, and that it was engrossing the atten- 
tion of many able men. Mr. George C. Clausen, of the Sicilian 
Asphalt Paving Company, two years ago, had laid experimental 
strips in Bronx Park, New York, and this year was supervising 
the construction of a large stretch of roadway in that park, using 
the "Sicilian asphalto," and guaranteeing same for five years. He 
called the attention of the convention to the fact that many of the 
delegates would, within a few days, be going over the race course 
laid out by the Automobile Club for the race to be held on the 
225th anniversary of the founding of their neighboring "City of 
Brotherly Love," and that they would pass over a section of road 
treated with "asphalithic" surface, laid at the intersection of Bel- 
mont Avenue and the city line, by the Filbert Paving and Construc- 
tion Company, of Philadelphia. He said that he had on the previous 
day called on Mr. J. L. Rake, the general agent of the Barber 
Asphalt Paving Company, who had informed him that his com- 
pany was deeply interested in the subject of dustless roads, and 
had laid asphalt concrete in a number of cities and towns; their 
expert, Professor Clifford Richardson, who had complete charge 
of the laying of the experimental roadways, as one of the repre- 
sentatives of the United States government, and additionally as 
the representatives of the States of New York and the Amer- 



142 ASPHALTS. [chap. xx. 

ican Society of Civil Engineers, had just sailed for Paris to 
attend the International Congress, and so could not be present 
at this convention. The speaker said that he himself had a num- 
ber of experimental pavements under way, and that in view of 
the remarks of Mr. Beemer, the Deputy State Highway Com- 
missioner of Pennsylvania, on the scarcity of broken stone in his 
State, he would add that he had arranged for an experimental 
pavement to be laid with asphalt and slag. He had hoped to have 
had an oportunity of asking Dr. Cushman, while on the platform, 
of the latest results of the United States government investiga- 
tions on this method of construction. He said that contrary to the 
condition of affairs in the past century, this country was not now 
dependent on sources of supply from Europe, the West Indies 
or South America, and that the United States could now produce 
all the bitumens necessary for the boundless calls the future would 
necessitate for furnishing asphalt concrete. He said that a great 
many of our States could furnish liquid maltha or asphalt which 
could be refined to any consistency required, enumerating Cali- 
fornia, Texas, Indiana, Kansas, Kentucky, Ohio, Pennsylvania 
and possibly New York. He claimed that any oil with an asphal- 
tine and petroline base could be refined to yield a satisfactory pav- 
ing material, but that parafine base oil must be studiously avoided. 
In the discussion that followed the delivery of the address, Mr. 
Beemer said he doubted whether Pennsylvania produced a petroline 
base oil, and the speaker promised to make definite investigations 
on the question. A delegate objected that the author had not 
dwelt upon the subject of the necessary foundation, and the latter 
replied that he was addressing himself principally to engineers and 
public officials, who realized fully that a solid foundation was the 
prerequisite for any well-paved street or road. In reply to the 
question of cost of the asphalt concrete two-inch surface, the 
speaker stated that it would mean an additional expense of not 
over twenty cents per square yard above the cost of an ordinarily 
constructed macadam road. 

On his way to attend the First International Congress of Road 
Builders, held in Paris, Mr. Samuel Hill, of Seattle, Wash., who has 
given many years of his life, and many dollars from his purse to 
foster the idea of macadamizing the roads of the United States, and 
particularly of his home State, was accompanied by two other 
delegates, Mr. R. H. Thompson, city engineer, of Seattle, and Mr. 




DETAIL OF SPRINKLER ATTACHMENT FOR OILING. 
W. H. Dunn, Superintendent of Parks, Kansas City, Mo. 



'ASPHALTS' 



ASPHALT SURFACING. 143 

Samuel C. Lancaster, Professor of Good Roads in the Washington 
State University. 

Mr. Hill, who is president of the Washington Good Roads 
Association, said: "Many delegates from every State in the Union 
were to attend the congress, Mr. Parker, president of the Massa- 
chusetts Highway Commission, and Mr. Fletcher, secretary of the 
commission, being among the number. 

"There is little use of my reciting the history of road building 
to you," said Mr. Hill, to a New York Herald reporter, "how it 
began with the Romans, how Napolean carried the matter along 
and all that, but I do want to say that France led the world in road 
building until a few years ago, when its highways began to de- 
teriorate, and that is the primary reason for the coming congress. 
In England there came the Telford process of road construction, 
and the Macadam, which, however, is totally different from what 
we understand by that term to-day. But, on a broad plane, I 
should say that the Macadam process carries out the theory of 
building a tight roof over a dry cellar. 

"I take it that the building of good roads is the most im- 
portant question that confronts the American people to-day. Every 
man, woman and child must use the highways at some time, 
whether afoot, on horseback, in a road wagon or in automobiles. 
The first man to call attention to the need of good public roads 
was A. J. Cassatt, now dead, and he was followed by James H. Mc- 
Donald, of Connecticut, who is president of the American Road 
Makers' Association. Understand at the outset, please, that this 
work of ours is only for the betterment of the country and that no 
man who has given time and thought to the project has done other 
than to put out money from his own pocket, with no hope of ever 
getting it back,, much less of viewing it as an investment. 

"Of the men who are to accompany me as delegates to the 
congress from Washington Mr. Thompson is one of the ablest of 
municipal engineers, and it was he who recognized the fact that, in 
the building of asphaltum roads any material having more than 
three per cent of fixed carbon would be injurious. His ideas were 
put into operation, each consignment of asphaltum was tested. 

"Mr. Lancaster has the chair in the department of Good Roads 
in the Washington State University, the first institution to establish 
such a course. It is a popular one, too. It had one hundred and 
twenty-five students in 1907, and this year it began with no less than 



144 ASPHALTS. [chap. xx. 

two hundred men in the class. We think in Washington that we 
have the best laws in the world as far as the making of good roads 
is concerned, for they have been compiled with the greatest care. 
Mr. Lancaster is carrying on a great educational work. We have 
organized bureaus for the dissemination of information about the 
State roads, and have opened a schoolhouse campaign where lectures 
are held and photographs and lantern slides showing the highways 
throughout the State and those in foreign countries, which I have 
gathered in my many journeys, are shown to those who attend. 

"When I became interested actively in the subject, about four 
years ago, I made up my mind that I would ascertain just what it 
cost one of our farmers to haul along the roads for one mile garden 
truck and other material weighing one ton. For on the farmer 
principally falls the burden of our bad roads. I learned that be- 
cause of the poor roads the United States lost, with the setting of 
the sun every day, nearly $3,000,000 which might be saved were 
the roads in proper condition. Just think of that ! And yet not a 
cent has come from the federal administration for the betterment 
of these roads. Some States, as Washington, and a few others, 
have appropriations, but not in proportion to the calling necessity. 
Then we began to get busy in our State of Washington. 

"We put the convicts at work and we found the process was 
a great success. Each convict netted to the State $4.03 for each 
day of work, which amounted to something. And not one convict 
turned out to this task tried to escape. North Carolina led in this 
system of convict labor, and that was fifteen years ago, and now it 
has eighteen hundred miles of macadamized roads built by convict 
labor, and only two per cent, of the men employed in this way tried 
to escape. In Washington the majority of our roads are constructed 
over mountains and at a maximum grade of five per cent. This con- 
vict labor did not interfere with union labor, either, for with the con- 
struction of the roads there was more work for the union men in 
other branches of the task. 

"Let me tell you of our method in Washington. We build our 
roads usually about one hundred feet wide. First we have in the 
middle a strip about sixteen feet wide. On the bottom we take from 
the screen cubes of rock about two and a half inches. This rock 
is put down wet, and a ten-ton steam roller goes over it from the 
sides, to make it cement and rise high in the middle. Then comes 
rock one-half the size of the other, and then the rock three-quarter 




36 



"ASPHALTS* 



ASPHALT SURFACING. 145 

inch cubes. Over this is poured asphalt, melted to about one hun- 
dred and eighty to two hundred degrees Fahrenheit, and over all 
this is thrown the fine pebbles. Then the steamroller gets to work 
again. Parallel to this strip we make a path of light material, 
designed for horses and vehicles ; alongside that comes a bridle path, 
for equestrians only, and then comes another strip of grassy lawn, 
with flowers and trees. We maintain that strip in all strictness. 

"In contrast with this let me tell you that in the Bois de Bou- 
logne, in Paris, a road was put down last year, and that now it is 
full of holes and worthless, and that the automobiles which passed 
along it raised such clouds of dust that the grass disappeared and 
lour trees which for years had been the pride of Parisians were 
killed. The Chief Road Engineer of Paris has told this to us in a 
report and he has asked the visitors to the congress to view this 
worthless road. 



Chapter XXL 
MUNICIPAL ASPHALT PLANTS. 

THERE are today in America Municipal plants operated in the 
following cities : Winnipeg, Man. ; Columbus, O. ; Dayton, 
O. ; Toledo, O. ; New Orleans, La.; Toronto, Ontario; Detroit, 
Mich. ; Allegheny, Pa. ; Omaha, Neb. ; and Seattle, Wash., has lately 
contracted for the erection of a plant.. In the October, 1908, issue 
of the "Municipal Engineering" the following interesting data was 
given by that magazine, which for so many years has given the 
closest attention to matters pertaining to the asphalt industries 

It is said that the number of municipal repair plants is increas- 
ing gradually and a few of them have now been in use long enough 
to give some idea of the cost of operating them so that at least a 
preliminary comparison can be made with the contract system still 
in use in most cities. Such plants as those at Columbus, O., and 
Indianapolis, Ind., have not been in operation long enough to give 
more than a daily force and material account and the actual effect of 
idle time, accidents, depreciation, repairs, etc., cannot be given ex- 
actly. The figures from them will be given more fully when more 
reliable statements can be made. 

Under the contract system in some cities the price bid is per 
square yard of pavement replaced. The prices vary greatly, being 
$1.65 in Minneapolis and St. Paul; $1.50 in Utica, N. Y. ; about 
$1.35 in Indianapolis in 1906; $1.35 to $1.50 in Columbus, O. ; 
$1.75 in 1897 in Rochester, N. Y., reducing gradually each year 
to $1.27 in recent years; $1.23 to 74 cents in Buffalo, N. Y. ; 89 
cents in Toronto, Ont. ; 66 cents in Indianapolis in 1907. The last 
named contract was the cause of much scandal on account of an 
alleged attempt to make up for the low price by over-measurements 
of areas of work done. 

Other contracts are per cubic foot of material placed, measure- 
ments being taken at the plant as the wagons are loaded. Under 
the contract system Brooklyn, N. Y., paid in 1905 6y cents per 
cubic foot for wearing surface and 25 cents per cubic foot for 




SPIKING UP OLD ROADWAY. 




SAME ROADWAY ONE DAY LATER. 
The Kelly-Springfield Road Roller used. 



37 



'AS P HALTS' 



MLXICIPAL ASPHALT PLANTS. 



147 



binder. Washington, D. C, paid 49 and 25 cents, respectively. A 
compression of one-sixth in laying makes the cost of the asphalt 
wearing surface in place in the pavement 78 cents per cubic foot in 
Brooklyn and 57 cents in Washington. 

The cost of laying asphalt in repairs by the Brooklyn municipal 
asphalt repair plant, which went into operation in June, 1907, has 
been 85.19 cents per cubic foot of wearing surface and 7446 cents 
per cubic foot of binder. These figures include materials, labor, 
transportation, supervision, fixed charges, maintenance and opera- 
tion of plant machinery and tools. If the thickness of the wearing 
surface is assumed at 2 inches, as in New Orleans, the cost of wear- 
ing surface per square yard becomes $1.28. 

It is not easy to reduce the reported costs of running the New 
Orleans municipal asphalt repair plant to the same basis as the fig- 
ures given above on account of numerous differences in conditions ; 
for example, absence of binder and greater thickness of wearing 
surface. The plant was used for laying new asphalt pavements as 
well as for repairing old pavements. Material and labor costs were 
kept separately, special charges against the asphalt plant as a whole 
were divided equally between the new and repair work and general 
charges against the paving and repair department were divided 
among the three sections, new, repair and miscellaneous work, 35 
per cent, going to the repair section. The "naphtha coat" was laid 
under about two-thirds the asphalt wearing surface deposited, and 
new concrete was put under about one-eighth of it. Deducting the 
cost of the concrete at 87 cents a square yard, the figure 
derived from the data regarding the work, the remainder will 
give the combined cost of naphtha coat and wearing surface 
for all the repairs made. This cost averages $1.03 a square yard, 
and does not include depreciation and interest on cost of plant, 
which may amount to 15 cents a square yard, making a total of 
$1.18. It is quite possible that this figure is too high, for new pave- 
ments, deducting cost of grading and concrete foundations, seem 
to have cost only 63 cents a square yard for the naphtha coat and 
asphalt wearing surface, as compared with $1.03 above. Repair 
work is more expensive than new work, but this difference of 40 
cents seems to be excessive and may be due to errors in either or 
both items made in the rather complicated distribution of costs. 

The first season of the Columbus, O., repair plant has not yet 
ended, but the operators of the plant have been obliged to fix a 



i 4 8 ASPHALTS. [chap. xxi. 

price for work done for other persons than the city and have set 
$1.25 a square yard as a price for such work, which, including all 
general and special items, plant and fixed charges, as well as main- 
tenance and operation, will cover the actual cost with as little margin 
as is safe in the absence of full data. 

Various reports from the Detroit, Mich., plant have shown 
83.6 cents per square yard cost of materials and labor and $1.05 
including all items of cost. 

In Allegheny, Pa., one report shows 75 cents a square yard as 
the cost of asphalt repairs for material and labor. 

An unofficial report from Dayton, O., indicates a cost of 57 
cents a square yard, which probably includes only materials and 
labor. 

The average cost in the Montreal municipal asphalt plant is 
$1.22 a square yard, including all work in connection with the re- 
pair. 

The Winnipeg municipal asphalt plant keeps detailed records 
of the work done. Records of laying new pavements are at 
hand. Deducting from the total cost for new pavements the cost 
of grading, sand foundation, concrete and binder, and 40 per cent, 
of the general charges, leaves the cost of laying the wearing surface 
87 cents per square yard. This is doubtless somewhat less than the 
cost of laying the same area of repair work. 

Allowing for the difference in conditions in these various cities 
it is fair to fix on about 85 to 90 cents per square yard as the aver- 
age cost of laying repair work for materials and labor, and say 
$1.15 to $1.25, including all charges in municipal plants. Cost of 
the various materials and of labor and the weather conditions pro- 
duce variations each way from these averages. 

Cities letting their asphalt repairs by contract have considered 
prices fair when they range from $1.25 to $1.50, according to local- 
ity. The difference indicates the cash saving to the street repair 
departments. 

Several cities have installed plants for doing their own asphalt 
repair work, not so much because they expected a reduction in the 
cost of the work, as for the purpose of securing complete control 
of the kinds and qualities of materials to be used and time of making 
repairs. In these respects the cities have found the results very sat- 
isfactory, enough so to warrant some increase in cost. However, 



a r 

V! JO 

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= 3 

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Cd "-3 

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38 



'ASPHALTS' 



MUNICIPAL ASPHALT PLANTS. 



149 



as the above figures will show, a reduction in cost has also resulted 
in nearly every case. 

Contractors for asphalt work express themselves frequently 
as being greatly pleased with the results from the municipal asphalt 
repair plants. They are usually able to induce the municipal plant 
to do repair work and small jobs at a reasonable price, which, while 
greater than the cost to them if their plant is running, saves them 
much expense if the plant must be started up for a small amount 
of work or particularly if a plant must be moved in from some 
other city. The city's street repair department is more than satisfied 
because it has complete control of the materials and workmanship 
and can thus insure good work done at the right time. 



Chapter XXII. 
ASPHALT WATERPROOFING. 

THE extent to which asphalt enters into waterproofing construc- 
tion can be imagined when it is seen that the Sicilian Asphalt 
Paving Co. in the New York Rapid Transit Subway, the Penna. 
R. R. Terminals and Tunnels in New York and New Jersey, the 
N. Y. Central and H. R. R. R. Terminals and Improvements in 
New York and the Sixth Ave. Subway of the Hudson R. Tunnel 
system laid over 20,000,000 square feet of waterproofing. 

The author has taken advantage of the courtesy of Mr. A. M. 
Tipper, of the Texas Co., and gives in full a paper* prepared by him 
dealing comprehensively with the subject of waterproofing. Mr. 
Tipper says that "the last ten years have witnessed a rapid increase 
in the field of cement usefulness. The formative character of con- 
crete and the ease with which it is adapted to a continually enlarg- 
ing number of structures have brought the concrete engineer in 
immediate touch with problems connected therewith which for years 
were largely — if not entirely — ignored. 

"The experiences of concrete engineers and contractors in 
their progress with the application of concrete to structure building 
of all kinds have shown them that in the practical field work, under 
the conditions oftentimes inevitable, with the natural imperfections 
which attend any work conducted in the mass, have proved to them 
that for many purposes to which concrete is at present applied it 
is necessary to protect the concrete structure and to prevent percola- 
tion through it. These experiences have also shown the architect 
and engineer that the field of cement usefulness would be greatly 
enlarged if there is supplied a perfect method of protection and 
waterproofing. 

"For this reason the waterproofing problem is at the present 
time attracting the attention of all architects and engineers ; and on 
account of its importance in the increasing application of cement of 



°A paper read by Mr. A. M. Tipper before the Cement Products' 
Exhibition Co., December, 1907. 



K 




39 



"ASPHALTS' 



ASPHALT WATERPROOFING. 151 

great interest to the cement manufacturers, while to the cement 
users the importance of the problem cannot be overestimated. The 
action of railroad companies, large construction companies and 
others in their investigation of waterproofing is evidence of the 
interest displayed in this subject and the necessity of adoption of 
waterproofing for the protection of the concrete structure. It may 
be said, in fact, that this protection is the necessary requirement 
for the consideration of concrete work as permanent. Climate con- 
ditions, atmospheric impurities, etc., may aid disintegration. Many 
propositions have been brought forward with the object of water- 
proofing in all kinds of ways by different methods, frequently with 
the result of disgusting the engineer with futile attempts at solving 
his problem or with dismay at the cost. 

"A large amount of the trouble experienced in the satisfactory 
waterproofing of concrete, and the consequent costly and incon- 
venient experiments, have been the direct result of a want of knowl- 
edge of the application suited to the local conditions which obtain in 
the structure to which the waterproofing is to be applied, a want 
of consideration of the requirements of waterproofing or a total 
disregard to the relative cost which the protection should bear. 

"Out of this mass of experiments and gradual formation of 
satisfactory waterproofing propositions has come the belief that the 
most satisfactory method of waterproofing concrete structures 
under all irdonary conditions, the most inexpensive and the most 
extensive in its possible applications is by the application of a 
bituminous coating on the surface of the concrete. It raises no 
question as to possible deleterious effects upon the concrete as do 
the compounds which enter the concrete mix, these being the sub- 
ject of considerable disagreement among engineering chemists as 
to their ultimate effect upon the concrete mass. 

"The application of the bituminous coat upon the concrete sur- 
face is a very simple, inexpensive proposition, readily handled with 
unskilled labor after a little training and satisfactory in its results. 

"Much poor waterproofing has been done in the past with so- 
called bituminous products of all kinds, and much distrust has fallen 
upon the method by reason thereof, either from a want of knowl- 
edge of the material or a want of consideration of the effect of its 
use. For a considerable period coal tar products were used in this 
connection and at the present time are still occasionally used. The 
properties and composition of coal tar products make them thor- 



I 5 2 ASPHALTS. [chap. xxii. 

oughly unsatisfactory as a waterproofing. They neither hold their 
ductility nor pliability, becoming brittle at comparatively high tem- 
peratures and soft at comparatively low temperatures, quickly losing 
the small bonding and elastic qualities they possess, and in a short 
time becoming absolutely worthless. 

"The first requirement of waterproofing covering for concrete 
is that it shall be impervious to water, and here the necessity of 
pure asphaltic bitumen for the purpose is thoroughly illustrated. 
Samples of two different kinds of asphalt taken and held in water 
for over one year at a pressure of 150 pounds to the square inch 
showed that one of these samples had absorbed no moisture, while 
the other had increased more than 129 per cent, in weight, owing 
to the absorption of water. Both of these asphalts claimed to be 
pure material and were guaranteed as such, yet evidently the one 
product was waterproof, while the other, without some readjusting, 
was decidedly porous. Pure asphaltic bitumen, that is, with over 
99 per cent, pure bitumen in its composition, should show no ab- 
sorption of moisture at all, presenting an absolutely impermeable 
surface. A further important requirement in bituminous water- 
proofing is its range of ductility, and here it is necessary to state 
that the fact that the product presented for waterproofing is pure 
bitumen does not necessarily include a high range of ductility or a 
particularly brittle point. The proportions of the petrolenes and 
asphaltenes composing the bitumen may vary, in which case the 
brittle point and range of ductility may vary. It is therefore essen- 
tial for the protection of the user that the range of ductility be 
asked for. 

"It is necessary that the bitumen be of sufficiently high melting 
point to insure its remaining solid under any of the conditions of its 
work, and it is just as imperative that it should remain pliable 
under any of the conditions. This makes it evident that the water- 
proofer should be conversant with the local conditions of the work 
his material will be against on any particular proposition. 

"In one test asked for the waterprofing was spread one-fourth 
inch thick on burlap, placed against a strong grating arranged in 
a testing machine provided with a pump for pumping ice water, in 
which was floating crushed ice. The specifications called for the 
waterproofing material withstanding a pressure of 10 pounds with- 
out the coating becoming brittle and cracking or passing water and 
that it should not melt below 225 degrees Fahrenheit. All samples 



P 




40 



'ASPHALTS' 



ASPHALT WATERPROOFING. 



153 



but one broke at seven pounds. The successful sample stood 10 
pounds pressure, which was then continued for twenty-four hours, 
at the end of which time it showed no defect. It was then deter- 
mined to conduct a breakdown test, which resulted in the sample 
withstanding a pressure of 300 pounds, when the packing blew, but 
the waterproofing still remained intact. 

"The waterproofing bitumen must therefore be pure and have a 
long range of ductility, and as an important corollary the water- 
proofing manufacturer must be able to suit his material and applica- 
tion to local circumstances and conditions. 

"It is very evident that to provide a waterproof floor for a 
warehouse where there is heavy trucking, etc., over it, is a different 
proposition from waterproofing a bridge floor, and it is equally as 
evident that the method of application in the case of the railroad 
bridge, where the headroom between floor and rail is small is a 
totally different proposition from the bridge, where the headroom is 
14 to 20 feet. 

"Briefly, the ordinary method of waterproofing by using a 
bituminous coating and the one used under a number of conditions 
is by the application of a priming coat of paint, which has light 
enough body to enter the pores of the concrete and form an anchor- 
age for the heavier bituminous coat. On top of this is mopped a 
hot coat of pure bitumen. This coat is of varying thickness, accord- 
ing to the work, from one-sixteenth of an inch on a concrete roof to 
one- fourth or one-half inch for bridge floors and deep foundations. 
Where the coating is exposed to the effect of cutting or chipping 
some reinforcement through the coat or some hard mastic mix is 
necessary. For vertical structures where the cutting effect is not 
accompanied by heavy load the reinforcement of the coating by the 
application of a single ply burlap is sufficient. Where, however, 
the waterprofing is horizontal and there is a cutting load above, it is 
often advisable to use a mastic mix. 

"The following specifications for the asphalt will insure good 
material for this work: 

"Asphalt shall be used which is of the best grade, free from 
coal tar or any of its products, and which will not volatilize more 
than one-half of 1 per cent, under a temperature of 300 degrees 
Fahrenheit for ten hours. 

"For metallic structures exposed to the direct rays of the sun, 
the asphalt should not flow under 212 degrees Fahrenheit and 



154 ASPHALTS. [chap. XXII. 

should not brittle at 15 degrees below freezing Fahrenheit when 
spread thin on glass. 

"For structures underground, such as masonry arches, abut- 
ments, retaining walls, foundation walls of buildings, subways, etc., 
a flow point of 185 degrees Fahrenheit and a brittle point of zero 
Fahrenheit will be required. 

"The asphalt covering must not perceptibly indent, when at a 
temperature of 130 degrees Fahrenheit, under a load at the rate 
of 15 pounds per square inch, and it must remain ductile at a tem- 
perature of 15 degrees below freezing Fahrenheit on metal struc- 
tures, and at zero Fahrenheit on masonry structures under ground. 

"In the application of coatings requiring a hard surface the 
finishing coat should be sprinkled with a layer of hot washed roofing 
gravel torpedo sand or slag to provide a hard surface. If this hard- 
surfaced waterproofing is required of considerable thickness, the 
asphaltic concrete of asphalt mastic and grit is the best method of 
waterproofing. 

"Asphalt is undoubtedly the oldest waterproofing known and 
was used centuries before the Christian era began. It has proved 
itself a thoroughly satisfactory coating, taking care of the expan- 
sion and contraction, and providing a pliable and ductile water- 
proofing, sealing up the pores in the concrete, covering hair cracks 
and checks, retaining its qualities for many years without deteriora- 
tion. 

"Its insulating qualities increase its value in an age when con- 
crete and steel structures are being continually used in places where 
the mtal may be subjected to electrolitic action." 

"Callendrite" — (Callender's Pure Trinidad Lake Bitumen 
Sheeting) is extensively used on 

Waterworks — For lining open and covered storage and serv- 
ice reservoirs, filter beds, valve towers, aqueducts, &c. 

Old leaking reservoirs or filter beds can be made absolutely 
watertight by its use. 

On Roads — For covering bridges, viaducts and arches, lining 
subways ; also for girder seatings. 

On Sewerage Works — For lining settling and filtering tanks, 
culverts and conduits, sewers, &c. 

On Gas Works — For lining gas holder tanks, &c. 

In Mining and Colliery Works — For lining pit ponds, tanks, 
storage and condensing reservoirs, &c. 




41 



'AS P HALTS' 



ASPHALT WATERPROOFING. 



155 



In Electricity Works — For lining cooling ponds, trans- 
former chambers, cable subways, dynamo bed foundations, &c. 

In Cold Storage Construction — For lining chambers for 
insulating purposes, &c. 

The advantages of using "Callendrite" for making watertight 
the earthwork embankments of open storage and service reservoirs 
will be apparent to the engineer, both from an economic and a struc- 
tural point of view. 




The sketch A, which is a section of an ordinary earthwork 
embankment with a clay puddle core, shows that the water will 
reach the face of the puddle before it meets with resistance; so 
that, in spite of the existence of the inner bank (1), the only 
effective resistance to the pressure of the water is afforded by out- 
side bank (2) Should the puddle get damaged, either by settlement 
or by the depredation of rats or other vermin, the efficiency of the 
reservoir is destroyed. The arrow on the sketch shows the direction 
of the pressure of the water. 

If the same reservoir were constructed with "Callendrite" as 
shown in Sketch B, it will be seen that, whereas in the former case 



SKETCH B. 




only one-half of the embankment offers effectual resistance to the 
thrust of the water, in Sketch B the whole of the embankment is 
brought into action. In addition to this, the direction of the thrust, 
as shown by the arrow, is such as to render the structure more 
stable, as it now has less tendency to overthrow the embankment 



156 



ASPHALTS. 



[chap. XXII. 



or to make it slide, and at the same time tends to make the embank- 
ment more homogeneous and to bind it closer to the ground at its 
base. Therefore, when Callender's Sheeting is employed, it is evi- 
dent that the section of the embankment can be considerably modi- 
fied, and a large reduction obtained in materials and cost. The 
saving in materials is especialy important in situations where the 
amount of excavation is small and the expense of procuring suitable 











material for constructing the embankment consequently forms an 
important factor in the total cost. 

Where "Callendrite" is used, it is only necessary to line the 
inner slopes of the embankments and the floor of the reservoir with 
a thin layer of concrete, so as to form an even surface for the sheet- 
ing, and then to cover the latter with 3 inches of concrete as a pro- 
tection from mechanical damage The thin layer of concrete cover- 
ing the sheeting which lines the inner slope of the embankment is 
prevented from slipping by the construction of a concrete toe at the 
foot of the slope, as shown in Sketch B, which at the same time 
prevents any tendency of the inner section of the bank to slip or 
spread. In short, the use of 'Callendrite" not only renders storage 
and service reservoirs absolutely watertight, but secures perfect 
solidity and great economy in their construction. 




42 



"AS P HALTS' 



ASPhALT WATERPROOFING. 



157 



In the construction of covered service reservoirs "Callendrite" 
is very serviceable, as its employment as a lining entirely dispenses 
with the necessity of costly outside trenches filled with clay puddle. 
As will be seen by the accompanying sketches, the main walls can 
be built in concrete, the sheeting being applied to the inner face and 
supported by an inner lining of 4^ -in. brickwork or 6-in. of fine 
concrete. The bitumen sheeting covering the floor of the reservoir, 
which is continuous with the sheeting lining the walls, is protected 
by 3 inches of fine concrete, by a course of brick on edge, or by 
paving stones, according to the requirements of the case 

Realizing that felt did not render a sufficiently strong fabric 
for waterproofing, Mr. H. R. Wardell, of the Barber Asphalt Pav- 
ing Co., on a visit to Germany obtained the idea of what he con- 
sidered a possible improvement on Callendrite and his company are 
manufacturing the Positive Seal Fabric, which is a saturated and 
coated burlap. This material is used in connection with Positive 
Seal Liquid or Solid Cement, as the case demands, in layers or plies. 
It is strong and resilient. It will give and twist, bulge, expand or 
contract, but never break, and so long as it does not break it will 
positively seal against water. This fabric has a much greater 
tensile strength than any felt made. For waterproofing, roofing 
or dampcoursing specify the construction the same as when using 
felt, except one-half the number of plies to get the same results. 
It is supplied in rolls of 300 square feet. 



Chapter XXIII. 
ASPHALTS IN ROOFING. 

OVER thirty years ago the author had a year's experience with 
the Warrens, who, at that time, had just started the use of 
asphalt in place of coal tar residuum for asphalt roofs, and with 
interest he now recalls his visits, in company of the late Samuel M. 
Warren, to architects' offices when they carried with them a segar 
box containing a little alcohol cooking machine with which they 
gave practical demonstrations of how the volatile oil of coal tar 
pitch evaporated and left dust, while the asphalt retained its elas- 
ticity and body under similar heat. The Warrens manufactured 
their asphalt felts at Sixth street, Long Island City, and on the 
south side of Seventh street the author, in conjunction with the late 
Edwin H. Wootton, built in 1892 the New York Mastic Works for 
the Compagnie Generale des Asphaltes de France, the sites of which 
are now owned by the Val de Travers Asphalte Paving Co., of 
London, and the Cyrus Warren Estate. 

Mr. Samuel M. Warren in 1845 was engaged in the business 
of laying pine tar roofs, and coal tars at that time were the waste 
products of the gas works. He conceived the idea of using coal 
tars to mix with pine tar pitches, and almost immediately thereafter 
used coal tar for saturing dry felt in making roofing paper. The 
first experiments and use occurred in Cincinnati. Mr. Warren was 
then a young man, and the opportunities for the development seemed 
so great that his brothers, John Warren, Cyrus M. Warren, Her- 
bert M. Warren and E. Burgess Warren, successfully and almost 
immediately enteeed with their brother upon contracting systemati- 
cally for the largest supplies of tars in the United States. The 
various brothers controlled at one time the tars produced in Cin- 
cinnati, St. Louis, New York City, Philadelphia, Baltimore and 
Washington, D. C. 

John Warren, who located in Buffalo, N. Y., is entitled to the 
credit for first distilling coal tar and making coal tar pitch ; and 
its immediate substitution for pine tar spread over the United 




43 



'ASPHALTS' 



ASPHALTS IN ROOFING. 159 

States. Hendricks' Architectural Engineering and Mechanical Di- 
rectory of the United States gives names and addresses of over 
seven thousand concerns now actively engaged in the laying of this 
kind of roofing. The business was almost immediately so prosper- 
ous that out of the revenues Mesrs. Cyrus M. Warren and Samuel 
M. Warren took courses in Harvard College, the latter afterward 
being professor of organic chemistry in the Massachusetts Institute 
of Technology and the author of that part of Dana's work on hydro- 
carbons which appeared in Dana's work on mineralogy. 

When petroleum came on the market the Warrens were among 
the first distillers in the United States, and Mr. Cyrus M. Warren 
became recognized as the best authority on the use of bituminous 
materials, and invented the process of fractional distillation of 
petroleum and coal tar oils, which process has given to the world 
all the numerous by-products. The commercial growth of the busi- 
ness up to 1870 was phenomenal, and all of the best energies were 
necessarily applied to the commercial development rather than to 
scientific investigation. In 1870 reverses came and found the War- 
rens with large contracts for tar, with a falling market and increased 
competition in the price of tar and manufactured goods. 

At this time competition made necessary the development of 
something new and better, and Cyrus M. Warren invented the 
asphalt roofing which has so long been manufactured by the Warren 
Chemical and Manufacturing Company, and they became the first 
large importers and refiners of asphalt in this country. 

The early failure of the coal tar bitumens in concrete construc- 
tion, owing to the price at which they were laid, furnished no in- 
centive for development, and a general view prevailed that concretes 
in which coal tar bitumens were used were deficient in every respect 
and should be excluded from all standard specifications. A monop- 
oly in the control of asphalt made it commercially profitable to decry 
even the best coal tar bitumens and to extend the use of asphalts. 
Yet it seems to be a fact that the early asphalt pavements were as 
great a failure as the early coal tar pavements. 

In recent years the Warrens have played a prominent part in 
the development of the asphalt pavements of the country. Mr. E. 
Burgess Warren was one of the organizers and one of the largest 
stockholders of the Barber Asphalt Paving Company, and for many 
years its vice-president. Cyrus M. Warren was the organizer and 
the president of the Warren-Scharf Asphalt Paving Company, and 



160 ASPHALTS. [CHAP. XXIII. 

in the management of this company and of the Warren Chemical 
and Manufacturing Company and other allied interests he was aided 
by his brothers, sons and nephews, and there have been engaged in 
the business over twenty-two Warrens, but today no member of the 
family is interested in the roofing business. 

One of the pioneers of the prepared roofing business is the 
Stowell Manufacturing Company, who, in the manufacture, unite 
the skill and experience developed by years of constant and careful 
attention devoted to the manufacture of asphalt roofings, exclu- 
sively, with the highest quality of raw materials available, without 
regard to their cost. 

The best quality of fibrous pure wool felt is saturated with 
genuine Trinidad Lake Asphalt and heavily coated with the same 
material of a stiffer consistency and into which is firmly imbedded 
a dense surfacing of crushed granite, felspar, ground asbestos fibre, 
cork, gravel, sand or ground mica nad slate. 

They produce ten varieties of surfaced roofings as well as sev- 
eral thicknesses of saturated roofing felts of one, two and three ply. 

Among these varieties of surfaced roofings are found those 
suitable for any class or style of buildings as roofing, sheathing or 
exterior surfacings. 

These products are made from natural Trinidad Asphalt ex- 
clusively, and no coal tar or coal tar products whatsoever are used. 
As a result these felts do not dry out or become stiff or brittle. On 
the contrary they are flexible and tough, yielding readily, and with- 
out injury, to contraction and expansion. 

This line of surfaced goods affords successful resistance against 
the action of weather, acids and gaseous vapors, as well as against 
ignition from flying firebrands, or burning cinders. They remain in 
good condition in any climate on flat or pitched roof or if applied to 
the perpendicular sides of buildings. 

Asphalts are used for "prepared" or "ready" roofings by a 
number of companies and under an endless variety of brands, fol- 
lowing the name of "Ruberoid," manufactured by the Standard 
Paint Company, a prolific list of roofings has been put on the market 
ending with "oid." The "Paroid" is a well known brand in which 
asphalt is partially used, and the "Flintkote," manufactured at 
Rutherford, N. J., by the Flintkote Manufacturing Company, is 
made with pure asphalts. The Trinidad Asphalt Manufacturing 
Company, of St. Louis, Mo., among its manufactures includes Rub- 




SINGER BUILDING. 
Hetzel's Rubber Roof Cement used in this building; supplied by J. 
Hetzel Estate, Newark, N. J. 



44 



'ASPHALTS' 



ASPHALTS IN ROOFING. 161 

bero. Among other users of asphalt for their roofings are the 
Barber Asphalt Paving Company, who make the "Genasco" brands ; 
the Lincoln Waterproofing Company, of Bound Brook, N. J. ; the 
National Roofing Company, of Tonawanda, N. Y., and several 
Western concerns. Malthoid, originally manufactured in Califor- 
nia, is now also made in New Jersey by the Standard Paint Com- 
pany. The Johns-Manville Company also use large quantities of 
asphalt in connection with their roofing materials. The efforts made 
by the Warrens to extend the use of asphalt for graveled surfaced 
roofs has not been sustained of late, but in cases of high-class work 
such as the New York Custom House and generally for United 
States Government work genuine asphalt is called for under a vitri- 
fied brick tile surface. 

The rock asphalt roofs so extensively used in Europe seem to 
have gone out of vogue in the United States, and in these days of 
roof gardens, it is, of course, necessary to have a roof not dented 
by chairs, &c. It is probable that reduction in cost of the native 
asphalts will cause a return to its use for ordinary graveled or slag 
roofings, as the cost will now compare favorably with what have 
lately been considered cheaper pitches. An ordinary slag surface 
specification would read about as follows : 

STANDARD TILE ROOFING. 

Specification. 

The grade of the roof, which should be at least one-fourth inch 
to one foot, should be formed by the mason, and the surface of the 
concrete finished smooth and hard by him before the roofer begins. 
The roofer should coat the surface of the concrete with hot asphalt 
cement in quantity sufficient to completely cover the same; over 
which lay five thicknesses of best quality asphalt roofing felt. The 
felt to be laid shingle fashion — beginning at the lowest point, with 
all laps stuck for at least two-thirds of their width with hot asphalt. 
Metal flashings shall extend out on this felt for four inches, and the 
roofer shall cover them with two felt strips securely cemented in 
place with hot asphalt. The entire exposed surface of the felt to be 
then coated wit hhot pitch, over which lay 6x9x1 -inch vitrified roof- 
ing tiles. 

Tiles to be laid in one inch of cement mortar — composed of one 
part of Portland cement (or equal) to three parts sand. Tiles to 



162 ASPHALTS. [chap, xxiii. 

be laid true to grade, joints broken, and the roof finished by grout- 
ing joints with liquid grout composed of one part each of sand and 
cement. 

ASPHALT SLAG ROOFING. 

Specification. 

On fireproof construction the surface of the concrete should 
first be coated with hot asphalt, in quantity sufficient to completely 
cover the same, then proceed as over wooden construction. 

On wooden construction the roof boards should be smooth, 
solid and laid closely together. Commence at eaves or gutter 
and lay full four thicknesses of best asphalt roofing felt, the 
felt to be laid shingle fashion, with one- fourth the width of each lap 
exposed. Securely nail on back of each sheet with nails and tin 
caps. All laps to be thoroughly stuck for at least two-thirds of their 
width with natural Asphalt Roofing Cement, applied hot. The en- 
tire surface of the felt then to be coated with the same material, 
into which shall be bedded clean, dry roofing slag. 

Ten gallons of asphalt and three hundred pounds of slag to be 
used on each one hundred square feet of surface. 




TOWER FOR SE'MI-PORTABLE ASPHALT PLANT. 



45 



'ASPHALTS' 



Chapter XXIV. 
ASPHALT FOR MANUFACTURE. 

THE uses to which asphalt may be applied as an ingredient 
in manufactures are multitudinous, and the author cannot 
pretend to enumerate them. Photography, ink manufacture and 
endless industries call for the use of this material to a greater or less 
extent. 

Mr. John A. Yates, a prominent civil engineer, who was in 
charge of the building of the forts at Fort Wadsworth during the 
Spanish- American war, said that it is a recognized fact that asphalt 
is such a thorough waterproof and insulating material that the 
Insulatine Company of New York are using it in considerable quan- 
tities in the manufacture of their insulating and electrical cements. 

Mr. David Szende, Director of the Hungarian Asphalt Com- 
pany, Budapest, while on a visit to New York about five years ago, 
gave the author some information on the making of varnish from 
Derna asphalt which may be interesting. The Derna asphalt is a 
high-class bitumen extracted from bituminous sandstone very 
similar to that found in the Indian Reservation. 

Take a quantity of the Derna mineral, and after breaking it into 
pieces as large a fist, put it into an open iron or copper boiler, 
which should be previously cleaned, especially from any greasy or 
fatty substances. A good fire will soon melt the material, which 
will become quite liquid by being stirred occasionally. It is advan- 
tageous when once liquid to let it boil for 2 or 3 hours without 
stirring, merely skimming it from time to time. In this warm state 
it should be put into a clean vessel and an equal weight of turpen- 
tine gradually added whilst stirring the material. Nothing further 
is required, the varnish is now ready for use. If it is wished to 
make a thicker kind of varnish, which will cover better, then add 
only 45 parts of turpentine to 55 of Derna. As long as the varnish 
is hot it remains in a thin state and only obtains the necessary con- 
sistency when cold. If, through being kept too long, the varnish 
becomes too thick it can be thinned by adding, in a cold state, a 



164 ASPHALTS. [chap. xxiv. 

little turpentine. The quality of the varnish depends solely on the 
class of turpentine used. It is observed further that when using a 
very hot fire the mineral at times ignites without coming into direct 
contact with the flames. Care should, therefore, be taken, and appli- 
ances held ready, to close as nearly as possible hermetically the 
boiler in case of the material taking fire. The Hungarian Company 
use a wrought iron cover and sand to fill any crevices. It does not 
matter if sand falls into the material as it will sink to the bottom 
of the boiler and can be removed. During the operation of boiling 
the material, and mixing it with turpentine, the boiler and vessels 
used must not be closed. 

An important industry is that of cork boards and insulating 
materials used extensively for breweries, cold storage warehouses 
and packing houses. 

Star Cork Boards are made by the United Cork Companies. 
They are manufactured from best grade, screened, granulated, nat- 
ural cork, every granule of which is coated with an odorless, water- 
proof compound, and compressed into board form. During the 
•entire process the cork is not subjected to extreme heat or great 
pressure as is the case with othed materials of a similar character. 
Excessive pressure destroys the cellular structure, and extreme heat 
destroys the life and vitality of the cork and its insulating prop- 
erties. 

Although cork is practically free from capillarity, they go a 
little further by using a special asphalt binder, which gives "Star" 
Cork Board even more insulating value than pure cork, inasmuch 
as the material they use is absolutely waterproof and impervious to 
moisture, preventing deterioration and decay. In addition it is 
highly aseptic and will not decompose nor cause the cork to disin- 
tegrate. Gums, glues or cements have no such capacity to resist 
moisture, and cork board made up with them will not be perma- 
nently satisfactory. 

"Star" Cork Boards are made 12 inches wide by 36 inches long 
in any thickness from 1 inch upward. They are squared to accu- 
rate dimensions thus making possible tightfitting work with no open 
joints. The boards can easily be sawed same as lumber to fit uneven 
o rirregular surfaces, thus further insuring continuous and com- 
plete insulation. On account of the compact form of the boards 
they possess superior structural strength and are adaptable to any 
construction of building. 




46 



ASPHALT 



ASPHALTS FOR MANUFACTURE. 1O5 

The electric companies use the material. Fuse works are among 
its purchasers, and varnish manufacturers all use it in some grade 
or another, varying from the high-class Egyptian to the cheapest 
American grades. 

One of the most important uses of asphalt not previously re- 
ferred to is that of the filling of joints of granite and brick pave- 
ments. For streets with steep grades granite block with asphalt 
fillers is the best construction, and such pavement is generally to be 
found on the piers and heavy traffic streets of European cities. Its 
advantages for this purpose may be briefly enumerated as follows : 

1. It provides for expansion. 

2. It provides for contraction. 

3. It is absolutely waterproof. 

4. It is permanent. 

5. Cracks are avoided. 

6. It leaves sufficient joints for foothold. 

7. It is easy to use correctly. 

8. The pavement can be cut without destroying the blocks. 
Any of the first-class bitumens will serve this purpose, but some 

care must be used in discriminating against too highly oxidized 
material and so-called asphalts produced by "secret process." 



Chapter XXV. 
ASPHALT MACHINERY. 

MACHINERY naturally enters largely into the asphalt industry, 
and much expense has been incurred in perfecting various 
improvements in working plants and refineries. A somewhat re- 
cent improvement is a sand dryer, which has been the means of 
quite a large saving in the cost of paving mixtures for sheet asphalt 
pavements. This was evolved from suggestions from several 
asphalt experts by the engineer of the Coatesville Boiler Works. 
No less than four of these dryers are now in use at the plant of the 
Cranford Paving Company, Brooklyn. The Filbert Paving Con- 
struction Company and Carey & Reed, of Philadelphia, also speak 
highly of the advantages gained by the use of this machine. 

These dryers have been developed during the past few years in 
the actual work of drying sand and similar materials. 

While in a general way they are the cylinder dryer in general 
use, they have a number of new features which are vitally import- 
ant to the satisfactory working of these machines, as they are built 
upon the broad principal of bringing the hottest products of com- 
bustion next to the dryest material, which is the reverse from the 
ordinary sand dryer. This is not only theoretically correct, but it 
has been found most excellent in actual practice. The drying is 
more rapidly and thoroughly done and there is practically no dust 
nor fine material driven from the dryer, owing to the fact that dust 
or fine aterial picked up by the blast is caught by the fresh ma- 
terial as it enters the dryer. 

Then again these dryers are made for hard and constant use. 
Every portion of the material is what has been found in actual prac- 
tice to be best for this character of work. At all points where the 
mechanism is affected by expansion and contraction due to the 
rapid heating and cooling of the apparatus, provision is made to 
prevent damage to any part of the structure. As a prominent user 
has suggested, after four years of constant use, it is a plain, prac- 




"A S P H ALTS' 



ASPHALT MACHINERY. 167 

tical, substantial machine and as nearly fool proof as a machine can 
be made. 

The shells are made perfectly cylindrical. The tires upon 
which they rest are steel forging turned all over to insure perfect 
balance, and these tires are secured to the shll by springs. The 
same arrangement secures the driving mechanism to the shell. The 
interior construction is forged steel, so arranged as to be practically 
indestructible, and the material is dropped through the hot flame 
and gas from the furnace in a continuous shower, thus subjecting 
every part of it to the heat in such manner as to dry it evenly and 
rapidly. 

The attachments for the dryer, including blower, blast gates, 
&c, are so arranged that the operator has absolute control of the 
temperature at all times. 

An asphalt plant with a capacity of 1,500 square yards per 9- 
hour day has been built for the city of Toronto, Ont., by the Warren 
Asphalt Paving Company, of Boston, at a contract price of $28,575. 
Its purpose is to enable the city to carry out all repair work 
promptly and probably lay a few small pavements each year. Com- 
plaints have been frequent in the past that openings in asphalt pave- 
enmts were not promptly repaired, and it is expected that no unrea- 
sonable delay will arise hereafter in executing "such work. The 
buildings have steel frames, galvanized roofs and sides, and rein- 
forced concrete floors. The machinery was recently described in a 
report by City Engineer C. H. Rust as follows : 

There are two self-contained rotary driers, manufactured by 
Warren Asphalt Paving Company, the revolving cylinders being 
40 inches in diameter and 19 feet 6 inches long. Draft is supplied 
by a 50-inch exhaust fan, which discharges into a Cyclone dust col- 
lector. The driers are fed by two chain elevators, and the hot sand 
or stone is discharged into an enclosed elevator and conveyed to 
steel storage bins holding 10 cubic yards each, situated on the sec- 
ond floor, the stone bin being fitted with a rotary screen. There is 
also a storage bin for limestone dust provided on the second floor, 
having a capacity of 4 cubic yards and fed by a dust elevator. The 
hot material and the dust are drawn by gravity into their respective 
weighing boxes which discharge into the mixer; the mixer has a 
capacity of 1,100 pounds of topping mixture. 

The asphalt cement is prepared in three enclosed melting tanks 
provided with mechanical agitation and having a capacity of 2,000 



168 ASPHALTS. [chap. xxv. 

imp. gals. each. The asphalt cement is elevated by air pressure to 
the asphalt weighing bucket, running on an overhead trolley to the 
mixer. The storage tank for flux has a capacity of 10,000 imp. 
gals. The flux is blown from it to the weighing tank on the first 
floor and drawn by gravity into the kettles. 

The asphalt barrels are hoisted to the charging floor by a barrel 
elevator. Power to the main portion of the plant is supplied by a 
ioxi2-in. engine, manufactured by the Erie Engine Works, and to 
the agitating tanks and barrel elevator by a 5X5-U1. engine, manu- 
factured by the Sturtevant Blower Works. Compressed air for 
forcing the asphalt cement out of the tanks and other purposes is 
furnished by a 6x8xi2-in. Knowles direct-acting air compressor. 
Steam is supplied to these engines by a 60-horsepower Star water 
tube boiler. Street and plant tools, including 8-ton and 5-ton steam 
asphalt rollers, five wagons, hand rollers, pitch kettles, &c, and 
twelve Wilkinson asphalt dump wagons, complete the equipment. 



Chapter XXVI. 
ROCK ASPHALT MAINTENANCE.* 

IN the discussion two years ago the author stated that Nelson P. 
Lewis, M. Am. Soc. C. E., Chief Engineer of the Board of 
Estimate and Apportionment of the City of New York, had con- 
sidered that rock-asphalt pavements were probably the best that 
had been laid. George W. Tillson, M. Soc. C. E., objected 
to it because he considered the maintenance charges on it exces- 
sive. The speaker, therefore, begs to state that rock-asphalt corn- 
prime has been laid in the United States in New York, Brooklyn, 
Long Island City, and Rochester, in New York State; Elizabeth 
and Perth Amboy, in New Jersey; Boston, Mass.; New Haven, 
Conn. ; Philadelphia, Pa. ; and New Orleans, La. 

The first comprime work was laid in Union Square, New York, 
in 1872. In August, 1897, 112th Street, from Fifth to Lenox 
Avenues was laid, and the city records show that in 1912 the cost 
of repairs on this street was only 6 cents per sq. yd. ; and 101st 
Street, from Lexington Avenue to Park Avenue, paved in July, 
1896, with Mons and Sicilian rock, bears no cost for repairs from 
1910 to 1913. Such durability seems to be unparalleled in the his- 
tory of street construction. On Dyckman Street, from Kingsbridge 
Road to the tracks of the New York Central and Hudson River 
Railroad, 8,000 sq. yd. of Seyssel and Sicilian rock asphalt were 
laid in the late fall of 1897, and the cost of maintenance for the 
4 years, 1910 to 1913, inclusive, was 3 cents per sq. yd., or less 
than 1 cent per sq. yd. per year. In 1901, between Park and Lex- 
ington Avenues, 35th and 36th Streets were paved with Seyssel 
and Sicilian rock asphalt ; on 36th Street no repairs were necessary 
for the 4 years, 1910-13. In the same year 13th Street, from 
Second to Third Avenues, was paved with Sicilian and Mons rock 
on an old stone foundation, and is charged with 14 cents per sq. yd. 
for 4 years' maintenance. In 1897, 106th Street, from Broadway 



*Read before the Am. Soc. C. E., January 24th, 1914. 



I7 o ASPHALTS. 

to Riverside Drive, was paved with Sicilian and Mons rock, and 
shows cost for repairs of 17 cents per sq. yd. for 4 years, a trifle 
more than 4 cents per year. 

To come to more recent times, it was decided in 1912 by the 
Department of Highways, under the advice of E. P. Goodrich, 
M. Am. Soc. C. E., Consulting Engineer to the President of the 
Borough of Manhattan, to lay a series of test pavements on Second 
Avenue, from Houston to 23d Streets. Rock asphalt comprime, 
or natural Sicilian rock powder was laid between 19th and 
21st Streets, and on inspection, in January, 1914, these 
blocks were found to be in fair condition, the chief imperfection 
being in the work adjoining the car tracks. This is not to be 
wondered at, as all rock asphalt experts, such as Malo, Delano, 
Walsh of Amsterdam, Bassett of London, and almost all engineers 
in Europe have decided that granite or other blocks should be laid 
longitudinally beside car tracks. The speaker recommends scoria 
blocks. The most noticeable of all the experimental pavements on 
Second Avenue is that of rock asphalt compressed blocks, between 
9th and nth Streets. These blocks were manufactured with 
an ordinary German brick machine, and did not receive the perfect 
compression obtained by the Val de Travers Asphalte Paving Com- 
pany in their works at Marseilles, Seyssel, and Cairo, Egypt, and 
elsewhere. However, the rock being pure crude asphalt powder 
before being pressed, simply spread under heavy traffic, and became 
virtually a monolithic sheet of rock asphalt, and it affords to-day 
as perfect a specimen of rock asphalt pavement as can be seen 
in any country. 

Mr. Delano, on the occasion of his visit to New York in No- 
vember, 1913, stated that the City of Paris had recently signed 
contracts for replacing wood blocks, stone sets, and macadam with 
700,000 sq. m. of rock asphalt pavement, to be laid during the next 
5 years. Attention is also called to the fact that, some years ago, 
Thomas Street, from Broadway to Church Street, and Trimble 
Place, from Thomas to Duane Streets, both private streets owned 
by fifty associates, were paved with Neuchatel Rock Asphalte Paves 
and coated with an asphalt rubber surface coat, only }i in. thick, 
which has stood the heavy traffic of those busy thoroughfares for 
several years. 

The speaker can prove that rock asphalt is the most valuable 
pavement in the United States. This is stated especially because 




*■■■■« il?r? 



■ !! 



M-lt-.rfi 



• i j ■ f 



DRIVEWAYS LAID WITH EUROPEAN ROCK ASPHALTIC 
PAVES BY L. L. WRIGHT. 




BASEMENT FLOOR OF ST. JOSEPH'S CHURCH, 

PACIFIC AVENUE, BROOKLYN, N. V. 

Laid with European Rock Asphalt Mastic by L. L. Wright. 



"A S P H A L T S' 



ROCK ASPHALT MAINTENANCE. 171 

so many engineers doubt that any European rock asphalt, such 
as laid in London, Paris, and Berlin, has ever been laid in the United 
States. The speaker is sorry that, owing to the short time allotted 
to him, he will have the opportunity to say but little about its 
history in America. 

The reason this subject of the practicability of the use of Euro- 
pean Rock Asphalte is so much more important than when the dis- 
cussion before the Society was held in 1912, is that the tariff on 
asphalt has been removed, and Rock Asphalte powder can now be 
purchased at a cost of $3 per ton less than in 1913, making a differ- 
ence of 25 cents per sq. yd. in the cost of the surface. Municipal 
plants can be supplied with the material, all ready for heating and 
compressing on the street, and no additional outlay for machinery is 
necessary. Both the Borough of Manhattan, which is now com- 
pleting its new municipal asphalt plant, and the City of Philadelphia 
are considering the advisability of doing their own repairs to rock 
asphalt streets. 

*In January, in the discussion on Col. Howard's paper on "Eu- 
ropean Rock Asphalts," the writer said: "I am sure all have been 
much interested in the paper delivered by Colonel Howard. It is 
a noticeable fact that army officers have been so much interested 
in asphalt pavements. Two chiefs of the U. S. Engineering Corps 
devoted much time to the subject. General H. G. Wright advised 
the paving of Pennsylvania Avenue with Neuchatel rock asphalt; 
General John Newton, on whose civic staff Colonel J. Hollis Wells 
and the speaker had the honor to serve, as asphalt experts and 
general inspectors of pavements, introduced Trinidad sheet asphalt 
for the lower sections of Madison Avenue. General Greene, 
U.S.V., left the army with the rank of captain to lead the Barber 
Asphalt Company's forces. General Averill claimed that he had 
to spend his old age as superintendent of the Soldiers' Home at 
Hampton, Va., through being defrauded of his patent rights by 
A. L. Barber. History is full of the tragedies of those who have 
been engaged in the asphalt business. 

"As Highway Commissioner Carlisle stated, revolutions have 
been fostered, and bribery, corruption and fraud have been in the 
wake of asphalt corporations. Fortunately, the European asphalt 
companies have been absolutely clean in all their transactions. 



*Read before the Highway Engineering Course, Columbia University, 
January 24th, 1914. 



I7 2 ASPHALTS. 

"Rock asphalt as pavement was first laid in the United States 
in New York, in the fall of 1872, by the North American Neuchatel 
Rock Asphalt Paving Company, the Earl of Dunraven, one of the 
directors, being in New York at that time. Orville Grant was the 
Chicago agent, E. E. Glaskin, general manager, and the speaker, 
agent of the company for Boston. The asphalt comprime was laid 
on a Portland cement concrete; about 1880 this asphalt comprime 
was removed and taken to the plant of the New York Mastic Works, 
then at the foot of East 19th Street, crushed, powdered, and, with 
the addition of asphalt flux made into mastic, which was then ap- 
plied in the coule form on the former concrete foundation; this 
work being supervised by E. H. Wootton and myself. In 1876 the 
District of Columbia Commissioners under advice of General H. G. 
Wright, Chief of Engineers, decided to pave Pennsylvania Avenue 
from the Capitol to Sixth Street with Neuchatel rock asphalt and 
the work was done under the supervision of Matt Taylor, as re- 
ceiver for the North American Neuchatel Rock Asphalt Paving 
Company. A few years later, Captain H. R. Bradbury was sent 
to this country by the parent company, the Neuchatel Asphalt 
Company of London. He laid rock asphalt pavements in front 
of the Brevoort House and the old Hotel Brunswick, both on Fifth 
Avenue. About the year 1889, Madison Avenue was paved, I 
believe for over thirty blocks, with Sicilian Rock asphalt and 
several other streets were laid at the same time with Limmer 
asphalt by G. Knoche. In July 1896 Convent Avenue from 145th 
to 146th Street was laid with Sicilian asphalt and is to-day in 
perfect condition after 17 years of traffic. In 1892 the Compagnie 
Generales des Asphaltes de France erected a rock asphalt plant at 
the foot of Seventh Street, Long Island City, under supervision of 
the late M. Miard, afterward the Compagnie's manager at Cairo, 
Egypt. Although Thomas F. Gilroy, the then Commissioner of 
Public Works had promised Mr. Delano of Paris, Managing Di- 
rector of the French Company, that they should have an oppor- 
tunity to bid on street pavement, the city specifications were so 
drawn that they could not bid on work and it was not until October, 
1895, that specifications allowed of its use; E. P. North, Mem. 
A. S. C. E., then being Water Purveyor, the official at that time 
in charge of street construction. Mr. North, however, insisted on 
an asphaltic binder being used, which was a totally unnecessary 
expense in the cost of construction." 



Chapter XXVII. 
ASPHALT MACADAM ROADS. 

AS I stated at Atlantic City in July, 1909, at the convention of the 
American Society for Testing Materials, it was* "rather dis- 
heartening to be informed (by a member of the Society) that the 
value of a bituminous cement can only be arrived at 'by service 
tests for a number of years.' As a practical worker for nearly 
thirty-seven years (in 1909) in asphalt construction for streets and 
roads and for asphalt concrete work as laid in foundations, I have 
no hesitation in stating that with the use of such quality of asphalt 
as has been hitherto satisfactorily used for standard street asphalt 
pavements and with the mineral aggregate heated and properly 
mixed an entirely satisfactory surface can be applied to old or new 
macadam roads." 

In 1909 I superintended the construction of School Street, 
Washington, D. C, and several roads under different specifications 
in Philadelphia with asphalt concrete finish. 

The best construction for asphalt macadam roads is that cov- 
ered by patents, and I cannot but suggest that contractors wishing 
to lay the best work should make arrangements to obtain conces- 
sions to work under Patent No. 727,565. Should they not wish to 
do so I can advise them that any one can lay the asphalt mixture 
to which the name "Topeka" has been applied, which has been used 
of late as a material suitable for resurfacing water-bound broken 
stone roads, as carrying a certain amount of fine stone, but not in- 
fringing the F. J. Warren Patent No. 727,505. It owes its desig- 
nation to a ruling in a case in litigation in 1910 in the U. S. Dis- 
trict Court for the District of Kansas, in regard to work which had 
been done in the cities of Topeka and Emporia, Kansas. In this 



*Page 611, Vol. IX., Am. Soc. for Testing Materials. 



174 



ASPHALTS. 



ruling Judge Pollock stated "that any pavements hereafter con- 
structed in substantial with the following formula, to wit: 

Bitumen 7—11% 

Mineral Aggregate passing 200 Mesh Screen 5 — 11% 

Mineral Aggregate passing 40 Mesh Screen 18 — 30% 

Mineral Aggregate passing 10 Mesh Screen 25 — 55% 

Mineral Aggregate passing 4 Mesh Screen 8—22% 

Mineral Aggregate passing 2 Mesh Screen.. Less than 10% 

sieves to be used in the order named, would not infringe the claims 

of said patent." 

All reliable and experienced engineers and chemists who have 
given close attention to the art of pavement and road construction 
know that certain basic qualities are needed in all asphalt paving 
cements and bituminous road binders. These basic and essential 
qualities are here arranged in tabulated form so that their separate 
importance, correlation and mutual complement of each other are 
apparent : 

1. Adhesiveness, or cementing strength 

2. Waterproofness, or freedom from injury by water 

3. Immutability, or freedom from deterioration on exposure 

to sun and air 

4. Cohesiveness 

5. Ductility 

6. Flexibility, or pliability 

7. Malleability, or ability to yield to shock without cracking 

8. Consistency at mean weather (jj deg. Fahr.) temperature, 

proper for the kind of pavement or road 

9. Minimum susceptibility to softening or stiffening during 

extreme weather temperatures 

10. Purity, or high percentage of bitumen 

11. Freedom from impurities of a vegetable or other deleteri- 

ous character 

12. Freedom from injury by heat necessary when melting for 

use. 
Waterproofness, or effect of water, is a very important quality, 
because pavements and roads are constantly exposed to rain and 
other moisture from above, by capilliary attraction from below, and 
by water which enters along and around rails and manholes, at 
curbs and other openings, and into slight cracks. If an asphalt 
cement is not waterproof, vegetable matter, soluble salts, earthy 




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•A S P H A L. T S* 



ASPHALT MACADAM ROADS. 



175 



and other matter in it will decay, the cement will lose its binding 
strength and the pavement will disintegrate. All specifications 
should have, like those of Washington, D. C, and some other 
places, a requirement preventing the use of asphalt cements affected 
or injured by water. 

A carefully prepared form of test made necessary to prove that 
bitumen contain these necessary qualifications is presented on the 
opposite page. 




BITULITHIC PAVEMENT. 
Dartmouth Street. Boston. Mass. Pavement laid 19( 
Photograph taken Sept., 1913. 




WARREN I TE ROADWAY. 
Fairfield Avenue, Fairfield. Conn. Laid over old macadam. 



A S P H A L T S' 



Chapter XXVIII. 
COLD LAID ASPHALT ROADS. 

DURING an experience in the supervision and direction of lay- 
ing asphalt streets and roads, in which I have now entered 
my forty-second year, I have found nothing so contrary to my early 
teaching that asphalt must be always used not only hot and with 
the greatest care as to exact temperature required for different 
asphalts and for different mixtures of asphaltic street and road 
concretes, binders, and fine street surfaces, as the fact, that for the 
past few years, satisfactory results have been obtained from the 
use of a cold mixture of specially prepared asphaltic cement with 
stone and sand aggregate. 

Among such methods of using cold construction are those 
employed by companies who have adopted what is known as the 
"Westrumite" process; in the Eastern States it is little known and 
in the Highway Engineering Department of Columbia University 
is found no record of this not unimportant branch of the asphalt in- 
dustry. The reason of the lack of interest in this construction is no 
doubt attributable to the fact that neither the asphalt nor the coal 
tar trust has any financial interest in its promotion. 

Several American visitors to the exhibition held in London 
in connection with the International Roads Congress last summer 
called attention to the fact that the American Westrumite Company 
had an instructive exhibit there, but had none at the National Road 
Makers' Convention Exhibition in Philadelphia last December; 
this was regrettable as the congress was believed to have been the 
largest attended one ever held in the United States. 

My attention was first called to "Westrumite"* as an emullsi- 
fied oil dust preventative, when on a visit to Newark on Trent, 
England, in 1904; but the method of this saponifying has since 
then been adopted for the more important feature of affording a 



♦"Asphalts," page 98. 



178 



ASPHALTS. 



cold asphaltic-cement or binder in a mineral aggregate for asphaltic 
macadam. 

In 191 1 I visited England and spent several weeks in obser- 
vation and study of the recent methods of road construction adopted 
in that country. In the summer of that year, "The Road Board" 
of England, through an arrangement with the County of Kent in 
collaboration with its County Engineer, Mr. Henry P. Maybury 
(since elected Chief Engineer of The Road Board), laid twenty- 
three experimental strips of pavement on the London-Folkestone 
Road between New Eltham and Sidcup. 

Through the courtesy of Sir George Gibb, Chairman of the 
Road Board, Colonel Crompton, Consulting Engineer, and Mr. 
Maybury, I was allowed every opportunity of inspecting, observ- 
ing, and making inquiries in regard to the work of all the different 
methods of road construction used in this experimental work. 

It might be remarked, en passant, that Mr. Samuel L. Hill, 
President of the National Road Makers' Association, stated in 
a lecture given before the matriculated students of Highway En- 
gineering at Columbia University last December, that the "Tarmac" 
and "Pitchmac" pavements seemed to him to be the most satis- 
factory of the pavements at the time of his inspection of the 
Folkestone Road work in the midsummer of 191 3. 

Both of these pavements having coal tar for their base would 
certainly have stood even better had asphalt-cement been used as 
the cementitious binder. 

During my inspection of the road in 191 1 I learned that while 
Messrs. Hooghwinkle, Anthony Brown and Partners were invited 
to bid on a section for Westrumite Asphalt Construction, their 
tender was not accepted, the price asked there for maintenance 
being considered too high.t 

On my return to New York in July, 191 1, I was informed by 
the very "progressive" Park Commissioner Stover that he had 
ordered a section of pavement at the Fifth Avenue entrance of 
Central Park to be laid with "Westrumite," and inspected the work 
at the time it was being laid. Due to facts, not reflecting on the con- 
tractors, some errors were made in delivery of stone, etc., which 
resulted in the work not being up to standard and it was relaid in 
1912; it is now in good condition, but a better sample of this con- 



t'The Road Board of England Report," July, 1911, page 10. 




•A S 1' H A L T S' 



COLD LAID ASPHALT ROADS. 179 

struction can be seen at the Ninetieth Street and Central Park 
West entrance to Central Park. 

Some excellent work of this construction is reported at Wash- 
ington. D. C, and Georgetown, and on Christmas day I inspected 
the "Westrumite" laid at Chevy Chase Circle and found that it 
compared more than favorably with competitive methods of road 
construction. 

As stated, this type of cold mixed asphalt concrete or macadam 
has not been used in the East to the extent that it has been in 
the Western States and in Canada, where excessive climatic changes 
are more trying to the life of such pavements. 

Enconiums on work done are found from such well-known 
road experts as Messrs. C. K. Wallace, City Engineer, East Chi- 
cago, Ind. ; J. Boyer, City Engineer, Crookston, Minn. ; H. Fergu- 
son, B.S., C.E., Stratford, Ont. ; A. McGillivray, Government 
Highway Commissioner, Winnipeg, Manitoba; Peter J. Lyons, City 
Engineer, Hammond, Ind. 

In Europe noticeable work has been laid in Antwerp and in 
Lambach and Graz, Austria. 

The possibilities of using such cold construction as this in 
places where it is difficult to transport machinery for heating 
asphalt and where work is required in small areas and inaccessible 
sections of country, makes the study and investigation of this 
cold process one of great interest to highway commissioners and 
other authorities having charge of road construction. 

The only patent in connection with Westrumite Asphalt Pave- 
ment is for the emulsifying of bitumens by which it is made, and 
even this is in no sense monopolistic as there are several inde- 
pendent companies within the United States and Canada manu- 
facturing and marketing this product at their own prices. 

The specifications under which it is being recommended for 
road construction are adaptable to the use of this particular ma- 
terial. There is, however, no obligation on the part of any purchaser 
to use these specifications. 

ttWestrumite Asphalt is adaptable to road uses in three dif- 
ferent methods of construction, two of which have one basic prin- 
ciple: the thorough and positive bonding together of mineral ag- 



ttGood Roads Year Book of American Highway Association, 1913, 
page 361. 



180 ASPHALTS. 

gregate ranging in size from two inches to one inch by the intro- 
duction of bituminous mortar composed of aggregate varying in 
size from that which will pass the one-half-inch opening to an 
impalpable dust in proper proportions to assure greatest density, 
mixed with a proper proportion of same asphalt. 

Although the principle used and the results are practically the 
same, the methods of their accomplishment slightly differ. 

In the one, on any form of solid and approved foundation 
such as concrete, crushed stone properly compressed or new or old 
macadam, the two inch to one inch stone is thoroughly coated 
with the Westrumite Asphalt and spread to a thickness of two 
inches, but in no way is to be compacted allowing the existence of 
the maximum amount of voids or air spaces around them. Upon 
these stones then is spread the mortar, as previously described, to 
a depth of one inch, having a consistency of very thick 
molasses, which on account of its fluid consistency largely fills the 
voids about the two-inch stone. Such voids as are not thoroughly 
filled in this manner are filled when the surface is rolled with an 
asphalt roller weighing from five to eight tons until the bituminous 
materials applied have been thoroughly compacted and left smooth. 

Upon this surface is applied a very light coat of same asphalt 
cement to fill and seal any small voids and interstices that may 
exist, on to which before the cement becomes set, is spread a thin 
layer of clean stone chips varying in size from three-eighths to 
one-eighth inch. The pavement is again thoroughly rolled and in 
about forty-eight hours, permitting the same asphalt to become 
thoroughly "set," is ready for traffic. 

The second method of construction, particularly adaptable to 
the resurfacing of new or old macadam roads, is identical to the 
method described, excepting that the two inch to one inch stone is 
not coated with Westrumite Asphalt. In this method the macadam 
road to be treated is scarified or harrowed to a depth of two to 
three inches, all particles of stone smaller than the three-fourths 
inch thus sifting to the bottom, leaving the coarse stone at the top 
uncompressed and containing maximum amount of voids. Upon 
this surface then is spread the bituminous mortar, as described in 
the foregoing, with the finish or flush coat handled in the same 
manner. 

The third method of construction consists of a surface treat- 
ment of macadam roads. 



COLD LAID ASPHALT ROADS. 181 

The road to be treated should be thoroughly cleaned of all 
small particles by brooming, until the coarse stone is exposed to 
view, when Westrumite Asphalt is to be applied by use of pouring 
cans or pressure distributer in proper quantity. 

Upon the asphalt cement thus applied, should immediately be 
spread stone screenings free from clay in varying sizes from one- 
half inch to impalpable dust in sufficient quantity to "take up" or 
absorb the asphalt. This is then thoroughly rolled until left smooth 
and compact. 

This surface is then covered with a very light application of 
asphalt into which is spread and rolled a light covering of clean 
stone chips varying in size from the three-eighths to one-eighth 
inch with the surface again thoroughly rolled. Traffic should be 
restricted for about forty-eight hours to permit the asphalt to 
become set. 

While this article treats almost entirely of one process for cold 
application there are of course other methods and other mixtures 
which can be used cold on the line of work. 

In Pennsylvania, New Jersey, and Ohio, several miles of road 
have been laid with a mixture of stone and asphalt binder mixed 
hot at the stone quarries but shipped cold and so spread on the 
roads. 

In the Folkestone Road experimental work, several cold appli- 
cations were made, among which was the crude Seyssel Rock 
Asphalt broken to small lumps and compressed by rolling. The 
work did not prove satisfactory and I continue to believe that rock 
asphalt should always be heated to obtain the best results. 

The "Tarmac" referred to is also shipped and applied cold, 
being constituted of slag coated and permeated while still hot from 
the steel furnaces with bituminous binder. Coal-tar has been one 
of the ingredients, but asphalt-cement of proper consistency would 
give better results. 

In this country** crude asphaltic sandstone, shipped as a cold 
powder, has given excellent results and in some sections of the 
country gives an opportunity for a moderate cost surface to an 
ordinary macadam road. 

A method not yet advocated in this country in the cold pro- 



**U. S. Department of Agriculture, Office of Public Roads, Circular 
No. 99, page 51. 



^2 ASPHALTS. 

cess of laying asphalt macadam is asphalt tarmac. It appears to 
be generally conceded that our visitors to the International Road 
Congress held in London last June considered that the most dur- 
able and desirable road in England was the tarmac. The writer 
saw the material being laid on the famous experimental section of 
the Folkestone Road between New Sidcup and Eltham. The sec- 
tion was laid in July, 191 1, by the Kent County Council under 
arrangement with the Road Board of England, under specifications 
of H. P. Maybury, the County Surveyor of Kent; Col. R. E. 
Crompton being consulting engineer to the Board ; Sir Charles Gibb 
Charman and F. W. Greig, resident engineers. 

The aggregate of "tarmac" consists of selected blast furnace 
slag produced for use at the Tarmac Company's works adjacent 
to the furnaces of Sir Alfred Hickman, Ld., Springvale, Etting- 
shall, near Wolverhampton. The author visited the works and 
made a careful study and examination of everything in connection 
with the preparation of this bituminous macadam for shipment 
to London. This slag is run in a molten state from the furnaces 
into suitable receptacles. In these receptacles it is shunted on to 
the company's premises adjacent to the furnaces and there allowed 
to remain until in the process of cooling it has solidified. It is 
then tipped on the slag selecting ground in blocks of about 5 tons 
each, broken by hand into pieces of suitable size, conveyed to the 
company's crusher, which turns out the different sizes from 2% 
inches to % inch, which is graded and then treated with the "Tar- 
mac" bituminous or asphalt composition. 

By this process the slag up to the time that is is impreg- 
nated with the Tarmac cement, has had no opportunity of absorb- 
ing moisture and therefore at the time of treatment is perfectly dry. 

Never having cooled, no reheating is necessary, and the tem- 
perature at the time of treatment with the Tarmac cement can be 
uniformly regulated. 

The slab used breaks with a very rough and uneven fracture 
and therefore has the greatest holding capacity for the bituminous 
cement. It is, moreover, sufficiently porous to absorb and hold a 
portion of the mixture. "Tarmac" is broken to the following 
gauges : 

2% inches (234 inches down to 1^ inches) 
i l / 2 inches (1^ inches to y 2 inch) 
Y% inch (% inch to Vs inch) 





58 



'A S P H A L T S 1 



COLD LAID ASPHALT ROADS. 183 

and shipped from the works in railroad cars ready for immediate 
use on the line of road work without heating, to any town in 
England. 

The binding cement used for coating the slag is the Tarmac 
Company's special bituminous cement, or a pure asphalt. The 
Ettingshall works have a complete distillation plant, and the mix- 
ture is prepared to certain uniform chemical and physical standards 
which are known to give the best results as regards binding, 
strength, durability and resistance to atmospheric changes. 

Upon the prepared road surface a bottom coat of 2^4 inch 
gauge material is applied and consolidated to a thickness of 1V2 
inches. Upon this an upper coat of 1^2 inch gauge material is 
applied to consolidate to a finished thickness of 1^ inches, making 
the total thickness of the double coating 4 inches. Each layer is 
separately consolidated with a steam roller, 6 to 8 tons in weight, 
and the surface of the top layer, after half-consolidation, is well 
brushed over with ^ inch gauge "Tarmac" so as to fill all inter- 
stices and is then rolled to an even and watertight surface, being 
afterwards covered with slag chippings at the rate of one ton to 
cover 250 super yards. 

No special tools other than those usually employed by local 
authorities are required. The after-consolidation which takes place 
under traffic varies with the original thickness and the nature of 
the traffic on the road. 

The thickness of 4 inches is that recommended for very heavily 
trafficked roads. For most main roads a smaller thickness at a 
reduced cost of construction may be used. 

This system of finished surface is free from dust in summer 
and mud in winter, is non-slippery, practically, noiseless, resilient, 
and impervious to ordinary atmospheric conditions or changes. 

"Tarmac" can be applied with equal success at any season of 
the year, some of the best work in Nottinghamshire having been 
laid in winter. Work can be proceeded with during wet weather, 
the only stoppage necessary being in drenching rain when men 
refuse to work, or when foundations of a soft or clayey nature have 
become saturated with wet. 

The material is impervious to wet when sent out from the 
works. There is, unfortunately, no method of giving the approxi- 
mate cost of the work in the United States, the Carnegie Steel Com- 



184 ASPHALTS. 

pany having held up a proposition to install a plant in connection 
with one of their works for a period of over two years. 

The figure obtained for the ''Tarmac'' work on the Folkestone 
Road was 97 cents per square yard, which included 6 cents per 
superficial yard for preparation of surface, but ordinarily it can 
be laid on the old road surface. The figure also included the cost 
of three annual dressings of ''Tarmac" liquid cement with slag 
clippings : which work although not essential to carry the road 
through its life, has by experience been found to be of great 
permanent benefit. 

It would seem probable that the cost of Si per square yard 
would not be exceeded in places where low freights prevail from 
the steel furnaces to towns or villages where cold laid pavements 
are the desideratum. As early as September, 191 1, the author re- 
ceived reports from England that the "Tarmac''' was the most 
satisfactory of the experimental strips of pavement on the Folke- 
stone Road, and the same satisfactory result was reported as exist- 
ing in July, 1913, by the Hon. Samuel J. Hill in his lecture last 
December before the graduate students of the Highway Engineering 
course of Columbia University. This material and the machinery 
for its preparation were originally patented by Mr. E. Purnell 
Hooley, the County Surveyor of Nottinghamshire. 

Another cold process for road surface construction is to be 
found in the natural Kentucky rock asphalt sandstone which in pow- 
der form can be shipped in open freight cars from Bowling Green, 
Ky., and applied to a levelled surface of an old macadam road at 
an economical figure for use in towns to which reasonable freight 
rates can be obtained. Detroit and Buffalo may be instanced. A 
report prepared by the office of Public Roads and issued June 30th, 
1913. says in regard to the experimental stretch of pavement laid 
at Bowling Green, Kentucky 7 in 1907: 

"The surface in general remains intact, smooth and hard, but 
bears evidence of not having had any attention. The slight defects 
found can be repaired at a very small cost and the section thus 
put in excellent condition.'' 

This is a good report after six years of service. 

The Texas asphalt rock from Uvalde Co. can also be pow- 
dered and shipped to sections where moderate freight charges can 
be obtained, and should give even better results than the Kentucky 
as it is a limestone in place of a sandstone. 




A S P H A L T S' 



Chapter XXIX. 
BITUMINOUS ROAD SURFACES.* 

IN 1909 I was elected as the delegate to the American Road 
Makers' Convention at Cleveland, Ohio, to represent the Quaker 
City Motor Club, that organization having always shown a keen 
interest in the building and maintenance of the "best roads." It 
was eminently proper that they should at the time mentioned seek 
to know of every improvement possible in road construction, for 
it was just prior to their holding the great Quaker City Motor Race 
in Fairmount Park, which was attended by one million visitors, 
Messrs. L. W. Page, Wilson, and the speaker being their special 
committee on the condition of the eight miles of road over which 
the race was to be run. The Quaker City Motor Club desires, 
through me, to make the following suggestions in regard to the 
construction of concrete roads : 

All concrete roads to have ample provision for expansion 
joints, such as those lately adopted at the navy yard, Norfolk, 
Virginia, manufactured from felt in sandwich form with bitumen 
in the center, or the cold asphalt prepared joints of straight bitumen 
formed in strips of regular width. All concrete roads to have 
a resilient, noiseless, waterproof coating. 

The statement in "Rock Products," issue of February 12, "the 
necessity of firm unyielding roads under present-day traffic con- 
ditions, has resulted in a wide demand both on the part of the 
engineering profession and the public, for more accurate and more 
scientific knowledge of the serviceability and permanency of various 
types of roads," is inaccurate insofar as it refers to "firm, un- 
yielding roads," which should be religiously avoided. The failures 
the speaker has witnessed in cement construction of roads, starting 
in 1886, when, as civic aide to Gen. John Newton, formerly Chief 
of Engineer Corps, U. S. A., he supervised the laying of a Portland 
cement concrete street, put down by an English corporation on 



* Read before the Concrete Road Conference, Chicago, Feb. 13, 1914. 



1 86 ASPHALTS. 

Beaver Street, north of the Produce Exchange, New York, and 
which did not last six months, down to the present time, convinces 
him that the Hassam Paving Company was correct when it changed 
its form of specification and called for a bituminous surface. 

The claim of the Dolarway Company for a patent for using 
material from the Barrett Manufacturing Company plants, has, 
the speaker believes, been disallowed. While the subject of bitum- 
inous material best suited for the surfacing of concrete roads is 
being considered, I should like to call the attention of highway 
commissioners to the fact that pure liquid asphalt, or maltha, can 
be obtained at about as reasonable a figure as Tarvia, Ugite, and 
other coal products, and with much greater lasting results. 

Another treatment of concrete surfaces has lately been mooted, 
and the speaker begs to bring it before the notice of this confer- 
ence. By the use of "Impervite" in the upper stratum of a con- 
crete road, not only a waterproofing process is obtained, but from 
tests made in Washington, it has been shown that a certain resili- 
ency results, added to an increased crushing strength. 

It must be emphasized that with a lean mortar, the perma- 
nency of the waterproofing compound is a very important point. 
That class of compound using stearate, leates, resinates, or other 
soapy material as a base, gradually washes out under prolonged 
action of water which slowly, but surely, dissolves even stearate 
of lime. A permanently waterproof surface is dependent on using 
a compound that is absolutely insoluble and unaffected by the 
elements. Bituminous waterproofing products belong to this class, 
and compounds have been developed which, as miscible with water, 
yet become absolutely insoluble after the mortar has set. This 
result is obtained by emulsifying the bitumen, which then mixes 
with water. 

Bituminous materials, so prepared, give a very high degree of 
permanent waterproofing. They are absolutely unaffected by salt 
water, brine, running water, boiling water, and ordinary chemicals. 

Liquid asphalt for oiling roads is applied not only to surface 
of macadam roads but also on ordinary dirt and gravel roads with 
excellent results. 

The presence of a large percentage of pure asphalt in the 
liquid gives it a quality necessary for making a fine type of road- 
way surface. 

The lighter or volatile constituent causes the asphalt to pene- 




PRIVATE ESTATE, GLENCOVE, L. I. 
Roads treated with Aztec liquid asphalt. 




2.1 STREET BETWEEN BROADWAY AND COLUMBUS AVE., MOW YORK < ' IT Y 
Aztec sheet asphalt pavement. 



'A S P H A L. T S' 



BITUMINOUS ROAD SURFACES. 187 

tiate well into the surface of the roadway. Upon evaporation of 
this volatile element, the asphalt remaining forms a strong binder 
and firmly holds the mineral particles of the roadway together 
making a hard, plastic and durable surface. 

Practice has shown that paraffine oils or semi-asphaltic petro- 
leum containing a high percentage of paraffine are of no benefit to 
a roadway. The temporary result of having the dust laid by such 
oils is of no value to the wearing qualities. 

Liquid asphalt is not only a road preservative but a construc- 
tive agent as well. Applied to a macadam roadway this material 
will make a compact and lasting surface. 

Liquid asphalt may be obtained in two grades, "A" and "B." 

"A" is for cold application and "B" is to be applied hot. 

Directions for Applying Liquid Asphalt "A." 

The surface of the macadam roadway should be carefully 
swept with stiff, hard brooms, removing all surface dirt as well as 
the stone or sand filling. On this rough, clean, dry surface liquid 
asphalt should be applied cold to the extent of about one-third of a 
gallon to a square yard. After the liquid has been applied, a 
covering of dustless screenings or coarse sand should be spread 
upon the roadway. 

On roads of very light traffic, the liquid asphalt can be applied 
in diminished quantities, in which case it would not be necessary 
to use the stone screenings or sand. When applied without the 
covering of stone screenings or sand the quantity of liquid asphalt 
applied should be at the rate of about one-eighth of a gallon to 
one-fifth of a gallon to the square yard. 

Directions for Applying Liquid Asphalt "B" 

Liquid asphalt "B" should be applied when heated to a tem- 
perature of about 250 degrees F. 

As in the case of the cold application, the surface of the 
macadam roadway should be carefully swept to remove all dirt 
as well as the stone or sand filling. On this rough, clean, dry 
surface a coating of liquid asphalt "B" is spread, using about 
one-fifth to one-third of a gallon per square yard. It should be 
applied by hand sprinkling pots or spread on by specially devised 
pressure sprinklers. It should then be covered with a layer of 
24 inch stone or dustless screenings and thoroughly rolled. It is 



^8 ASPHALTS. 

not advisable to make this application when the weather is wet 
or cold. 

Liquid asphalt has been used in treating roads in a number 
of towns in New York and New Jersey. The treatment does not 
consist in forming a bituminous carpet over the road, as this is 
Understood in Massachusetts for example, where heavy asphalts 
are applied hot to the road bed and form a distinct bituminous layer 
of asphalt and stone screenings. With the use of the liquid asphalt 
as described, on account of the lightness of the material there is 
an actual penetration of the oil into the material of the road and 
the heavier bitumens form a crust which increases in thickness with 
successive years' applications. 

The experience of the town of Islip, Long Island, is typical 
of the general method. Here liquid asphalt of about 20° Baume 
gravity was used. This material is a natural or "straight run" as 
distinguished from a "cut back" material. Consequently it is com- 
posed of hydrocarbons of more nearly uniform density than is 
"cut back" material. 

For about eight years the oil treatment has been used. Pre- 
vious to that the roads had been sprinkled with water by private 
contract, presumably at a high cost, as at times they required 
sprinkling five times a day. One treatment of oil a year has been 
sufficient. Last year about one hundred miles were oiled at a cost 
of about $8,500. The amount of asphalt used is about one-third 
gallon per square yard. It was applied by a Studebaker distributor, 
under power from a pump operated through chains and gears from 
the wheel. 

The most unique surfacing for roads that I have come across 
is one on a dirt by-road near Fort Stevens, in the District of Colum- 
bia near the Maryland line, where I found last February that some 
enterprising individual had covered about 150 running feet of sur- 
face with the material stripped from a slag roof — the paper surface 
of the roofing was uppermost and the slag and tar on the road top. 
The sun will doubtless melt the tar and the slag will become de- 
tached from the felt, which, presumably, will be blown away or 
possibly be raked off. 




ALBANY POST ROAD. NORTH TARRYTOWX. 
Laid with Hastings Asphalt Blocks. 




BOSTON POST ROAD. IN THE VILLAGE OF RYE. 
Laid with Hasting Asphalt Blocks. 



56 



«A S P H A L T S 



Chapter XXX. 
ASPHALT BLOCKS FOR ROADS. 

A CONSTRUCTION which may be used for the wearing sur- 
face of rural roads, is one that can be manufactured at a 
permanent plant, and shipped in block form to the site of the 
proposed improvement, ready to lay, and which can be obtained in 
small or large quantity at any time for extension or repairs. 

Many years ago the asphalt block was developed on the theory 
that crushed trap rock, on account of its pre-eminent hardness and 
inherent grittiness, made the best-known material for a roadway 
surface, the one thing needed being a cement, or binding material, 
to keep all the particles permanently in place. This was accom- 
plished by the use of an asphaltic cement to bind together the 
properly graded particles of crushed trap, the hot mixture being 
consolidated by tremendous pressure into blocks so dense and free 
from voids as to be practically non-absorbent. In the asphalt-block 
we have an asphaltic concrete, or macadam, mixed, in exact pro- 
portions, at a central plant, under conditions insuring uniformity, 
and receiving the compression necessary to produce a dense and 
non-absorbent material. 

The blocks thus made are ready for immediate shipment to 
the location of the proposed improvement, whether it be only a few 
hundred square yards or many thousand square yards. The ex- 
pense of shipment is no greater than would be the cost of shipping 
the crushed trap rock necessary for constructing an equivalent 
amount of ordinary macadam. 

As designed and manufactured for use on country roads, the 
blocks are five inches wide, twelve inches long, and two inches 
deep (5 in. x 12 in. x 2 in.), weighing about eleven pounds each. 

Not only has a special block been produced, but a special 
method of construction has been worked out, designed to utilize 
what is left of the worn and rutted macadam road as a foundation 
for the blocks. This is accomplished by scarifying the surface, if 



190 



ASPHALTS. 



necessary, filling up the deep ruts, rolling with a heavy steam roller, 
and laying upon the surface of the old macadam, a bed of cement 
mortar about one inch in thickness, to serve the double purpose of 
forming a firm, unyielding bed for the blocks, and binding them 
securely to the macadam foundation underneath. By this method 
the material used in the original construction of the road is not 
thrown away, but used as foundation for a permanent wearing 
surface. Where the old macadam is too thin, or too badly worn to 
be safely used as a foundation, it will be necessary to lay a con- 
crete base, but usually there is broken stone enough in the old 
macadam to supply what is needed for laying concrete. 

Another advantage gained by the use of blocks lies in the 
feasibility of laying a pavement of any desired width, contour, 
grade, or crown. It is feasible to pave one-half of the roadway, or 
only a narrow strip in the center, and extend the paved area at a 
later date as traffic necessities require, or as appropriations become 
available. It is not necessary to set curbstones or heading stones to 
border or define the paved area, since a row of stretcher blocks 
held firmly in place by a shoulder of mortar, answers the purpose 
perfectly and leaves the entire roadway surface smooth and 
uniform. 

This system of road construction for heavy travel inter-urban 
highways has now acquired a reputation for efficiency. The Albany 
Post Road running up the valley of the Hudson River and the 
Boston Post Road running along the shore of Long Island Sound 
have sections surfaced with these blocks. 

As stated in Chapter 26 the use of European Natural Rock 
Asphalt blocks, or as they are called in Europe, paves or slabs, is 
likely to become an important feature in road construction. The 
duty on Rock Asphalt Powder which was in 191 3 three dollars 
per ton, has been removed, and it is now possible to compress the 
blocks in the United States and sell them at a lower cost than can 
be made in any of the European capitals. The specifications for 
the imported slabs as laid on Thomas Street, New York, were as 
follows : 

The Portland cement concrete base to receive the paves should 
be either four (4) or five (5) inches in thickness, furnished in 
place properly struck off, smooth, parallel to, a specified distance 
of 2}i inches below the final grade. On this lay a one (1) inch 
cushion coat or bed of Portland cement and sand, mixed dry, in the 



ASPHALT BLOCKS FOR ROADS. . 191 

proportions of 1 to 3, of just sufficient thickness to level up the 
inequalities of the concrete base underneath, so as to afford a 
perfectly level surface for the paves. These paves are to be laid 
with the joints close together and, when all are laid, the surface 
of the paves is watered with a sprinkling can, so that sufficient 
moisture may penetrate between the joints of the paves to enable 
the cement and sand under the paves to set up. 

The entire surface of the paves is then covered with a rubber 
coat of European Rock Asphalt Mastic, laid about 3/16 inch in 
thickness. 

The object of the rubber coat is to close the joints of the 
paves while they are undergoing their ultimate compression under 
the traffic and also to afford an absolutely safe foot-hold to horses, 
etc., during wet or slippery weather. 

Owing to this coating being composed almost entirely of pure 
European Rock Asphalte, it forms a tough, rubbery coating which 
indents easily under the horses feet but does not break, thereby 
affording an absolutely sure foothold in turning and backing. 

These paves or slabs come in two sizes: 

8 in. x8 in. x 13^ in. and weigh about 7^ lbs. each. 
10 in. xioin.xi^ in. and weigh about 12% lbs. each. 

A project is on foot to utilize the Texas asphalt for the manu- 
facture of asphalt blocks, and there is no question but that with 
pressing machines established at the Uvalde mines, blocks could be 
manufactured which might be put on board at Galveston and 
shipped at a moderate cost for use at seaport towns in the United 
States, Cuba, the West Indies and South America. 



ADVERTISEMENTS. 



JOHN BAKER, Jr. 

REFINED ASPHALT 

FOR PAVING AND 
ROAD BUILDING 

And All Other Purposes 



NEW YORK OFFICE 
Whitehall Building, 17 Battery Place 



CHICAGO OFFICE 
Otis Building, 10 S. La Salle Street 



OTHER OFFICES 

BOSTON KANSAS CITY, MO. 

PITTSBURG MINNEAPOLIS, MINN. 

PHILADELPHIA DENVER, COLORADO 

BUFFALO BIRMINGHAM, ALA. 

RICHMOND ALBANY, N. Y. 



Representatives throughout United States and Canada 

WRITE FOR PARTICULARS 



AD VER Tl SEMEN TS. 



A proper connection. 



High standard requirements 



TEXACO 



PAVING 

WATERPROOFING 
ROOFING 





ASPHALT 



—Good work and satisfied customers. 



Uniform. Durable. 



Pure. 



Write to Dept. A. 



The Texas Company 

New York Philadelphia Providence St. Louis 

New Orleans, and Port Arthur, Houston and Dallas, Texas 



.iiviik'risi-vnNTS. 



WARRENITE THE PERMANENT COUNTRY ROAD SURFACE 




(Gravel) 



(Crushed Stone) 



(Oyster Shells) 



The above illustration shows vertical sawed cross sections of Warrenite, the permanent 
country road surface, using 
A— Gravel ) 

B— Crushed Stone \ Mineral Aggregates 

C-Oyster Shells ) 

All of which have proven to give satisfactory results. 

See illustration opposite page 176 of text. 

Warrenite is not a mere liquid coating but is a hard surface made of a dense mixture 

of stone heated and combined with bituminous cement and laid two inches in thickness. 

INVESTMENT versus SPECULATION 
BITULITHIC FOR CITY STREETS 

is an asset. It is an investment not a speculation. 

Investigate Bitulithic before determining to use inferior street paving. It is cheaper 
to have good pavement in the beginning than to contract for cheap constructions and be 
sorry in two or three years. 

There is no guess work in the construction of Bitulithic pavement. It is made of 
varying sizes of the best stone obtainable, combined with bituminous cement and laid 
under close laboratory supervision. You must realize that quality is remembered long 
after the price is forgotten. The character of a city is indicated by the condition of its 
streets. 

See illustration opposite page 176 of text. 

Bitulithic is— Unequalled in reputation. Bitulithic is— Unquestioned in quality 

Bitulithic is— Unrivalled in popularity 

Stationary Plants Railroad Plants 

Semi-Portable Plants Portable Plants 

We manufacture all styles of all capacities. 

We can give you just what you want when you want it and the most for you money. 

See illustration of Semi-portable Plant opposite page 48 of text. 

WARREN BROTHERS COMPANY 

Executive Offices: 59 Temple Place, BOSTON, MASS. 

DISTRICT OFFICES: 

New York, N. Y., Chicago, 111., Rochester. N. Y., Los Angeles, Cal., 

50 Church St. 10 So. LaSalle St. 303 Main St , West 926 Calif. Bldg. 

Portland. Oregon, Phoenix, Arizona, 

Journal Bldg. 204 Noll Bldg. 

Nashville, Tenn., Richmond, Va., St. Louis, Mo. 

606 First Natl Bank Bldg, Virginia Railway & Power Bldg. Railway Exchange Bldg. 



ADVERTISEMENTS. 



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SPHALT 



It is pre-eminently a high-grade asphalt % 
by every essential test. -® 



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Guillll 



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Laid extensively in the leading cities and ™ 
on many state and county highways. ^)| 



Aztec Liquid Asphalt 

For Preserving Roads 

Combines the features of a dust layer 
and road preservative in one. Equally suc- 
cessful on macadam, dirt, sand or gravel. 

The Interocean Oil Co. 
The United States Asphalt Refining Co. 

90 West Street, New York 

Chicago Philadelphia Baltimore Norfolk 

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ADVERTISEMENTS. 




Refined 
Mexican Asphalt 

Prepared in various grades for 

Sheet Asphalt 
Pavements 

and 

Bituminous Macadam 
Road Construction 

by either the penetration or 
mixing method. 

Standard 
Asphalt Road Oils 

Containing from 40% to 60% 
asphaltum. 

Specifications and other parti- 
culars on application. 

STANDARD OIL COMPANY OF NEW YORK 

Road Oil Department 26 Broadway, New York 



ADVER TI SEMEN TS. 



THE HASTINGS PAVEMENT COMPANY 

EXECUTIVE OFFICES 

25 BROAD STREET - NEW YORK CITY 

Works : Hastings-on-Hudson, New York 

Asphalt Block Pavements 

See pages 187-189 and illustrations opposite page 188 

Societa Sicula per l'esplotazione dell' Asfalto naturale Siciliano 

(Own Mines and Works at Ragusa, Sicily) 

Head Office at Palermo, Via Girgenti 3 

Sicily Natural Rock Asphalt, Powder, Mastic and Slabs 

Many millions of square metres in Berlin, Paris. Vienna, Bucarest, Glasgow, 

Cairo (Egypt) and Athens, also in Montreal (Canada) and U. S., have been 

laid with success since 1888. 

American Consulting Engineer 

T. HUGH BOORMAN 520 E. 20th Street, New York 

J. W. HOWARD, C.E.,E.M. 

27 Years Experience 

Paving Expert Engineer 

and Pavement Testing Laboratory 

EXPERT ON ASPHALTS AND THEIR USES 

1 BROADWAY NEW YORK 




THE STANDARD PAINT CO., New York, Bo.ton, Chicago 



ADVERTISEMENTS. 



INSULATINE COMPANY, INC. 

JOHN A. YATeS, C.E., President 
Manufacturers of 

Waterproof Sealing Cements, 
Paints and Compounds 

No. 1 BROADWAY NEW YORK 

Lewis M. Sheridan Benjamin F. Redner 

CENTRAL CITY ROOFING CO. 

Original Agents for Seyssel Rock 
Asphalt Mastic in Central New York 

See illustration opposite page 76 
OFFICE AND YARD 

COR. CANAL AND CATHERINE STS., SYRACUSE, N. Y. 

SAN ANTONIO BEAUMONT HOUSTON 

J. B. SMYTH, President CHAS. E. WALDEN, Secretary 

FRANK ALVEY, Treasurer 

Uvalde Rock Asphalt Company 

Producers of the Perfect Natural and Economical Road and Street 

Paving Material 

CONTROLS UVALDE ROCK ASPHALT MINES 

1506 Dallas Avenue HOUSTON, TEXAS 

See pages 44 and 191 and illustration opposite page 56 
ESTABLISHED 1860 

ESTATE OF J. G. HETZEL 

J. G. HetzePs Improved Asphalt Slag Roofing 

Hetzel's Elastic Roof Cement and Paints 

Used throughout U. S., and extensively in Europe 

See illustration opposite page 160 
OFFICE AND WORKS 

No. 67 MAINE STREET NEWARK, N. J. 



ADVERTISEMENTS. 



QUARTERLY PROCEEDINGS OF 

The American Society of 
Engineers, Architects and Constructors 

is one of the best mediums for advertising machinery and materials used 
in road construction and supplies of all kinds used in engineering 
work. For particulars as to terms for insertion of advertising, apply to 

T. HUGH BOORMAN, C. E., Secretary, 520 E. 20th St., N. Y. 

THE ASPHALT CONSTRUCTION COMPANY 

ASPHALT PAVING AND 
GENERAL CONTRACTING 

Office Plant 

207 Broadway, New York 137th St. and Madison Ave., New York 

Telephone, 3110 Cortlandt Telephone, 771 Harlem 

See illustrated page 12, opposite page 52 

ESTABLISHED 1872 

NEW YORK MASTIC WORKS 

L. L. WRIGHT, Gen. Mgr. 

European Rock Asphalt 

Crude Rock, Powder, Mastic and Blocks 
543 SMITH STREET 

BOROUGH OF BROOKLYN NEW YORK 

T. HUGH BOORMAN, Consulting Engineer 

See Illustration on Page 170 

FREE CATALOGUE OF BOOKS 

on 

Architecture, Engineering and Construction and Sample Copy of 

"ARCHITECTURE and BUILDING" 
Address, THE WILLIAM T. COMSTOCK CO. 

23 Warren Street, NEW YORK CITY 



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